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1

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

NASA Astrophysics Data System (ADS)

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

Moldovan, G.; Sikharulidze, I.; Matheson, J.; Derbyshire, G.; Kirkland, A. I.; Abrahams, J. P.

2012-07-01

2

Complete polarization analysis in the 1keV to 2keV energy range using a high-precision polarimeter  

NASA Astrophysics Data System (ADS)

The Beryl and YB66 crystals are proved to be suitable as analyzers in the energy range from 1.0keV to 2.0keV. The s-component reflectivity (Rs) of Beryl crystal reaches up to 10% with polarizing power Rs/Rp over 1000 at 1.1keV. The free-standing W/B4C multilayer has the phase shift over 5° with moderate transmission up to 1.7keV. The Bragg resonance width of the Beryl crystal is only 350 microradians at 1.1keV, and the incidence angle of the beam onto the crystal needs to be constant within 50 microradians or better. A high-precision polarimeter was used for the polarimetry experiment, and the complete polarization analysis of the APPLE II undulator at 1.1 keV and 1.56keV will be presented.

Wang, Hongchang; Dhesi, Sarnjeet; Bencok, Peter; Steadman, Paul; Maccherozzi, Francesco; Sawhney, Kawal

2013-03-01

3

Sputtering yields, range and range straggling in Al following Kr + ions bombardment in the energy range (20-160) keV  

NASA Astrophysics Data System (ADS)

The sputtering of Al metallic films by 84Kr + ions has been studied over the energy range (20-160) keV. Sputtering yield data have been extracted by means of the Rutherford backscattering technique (RBS) using a 2 MeV beam of 4He + ions. They have been compared to values derived by Sigmund's linear cascade theory, Yamamura's semi-empirical formula or by Monte Carlo computer simulation using the TRIM code. A fair agreement was observed between the measured sputtering yields and the predicted ones. The depth profiles of the implanted Kr + ions into Al have also been measured, and then fitted assuming Gaussian shape distributions, which allowed us to extract the projected range, Rp, and the associated range straggling, ? Rp. For the former stopping parameter, a very good agreement is obtained between experiment and the LSS theory predictions while the MC simulation also accounts satisfactorily for the measured data over the whole explored energy range, reflecting an adequate description of the projectile-target interaction by the universal potential of the Thomas-Fermi type assumed in the LSS formalism. In contrast, the ? Rp measured data show to be consistent with the predicted values only at E ? 60 keV but lie to ˜30% above them at lower energies. This discrepancy not caused by the sputtering effect relates to an incomplete evaluation of the range straggling by theory at low bombarding energies.

Mammeri, S.; Ouichaoui, S.; Zemih, R.; Ammi, H.; Abdesselam, M.; Chami, A. C.

2005-10-01

4

A study of 2-20 KeV X-rays from the Cygnus region  

NASA Technical Reports Server (NTRS)

Two rocket-borne proportional counters, each with 650 sq c, met area and 1.8 x 7.1 deg FWHM rectangular mechanical collimation, surveyed the Cygnus region in the 2 to 20 keV energy range on two occasions. X-ray spectral data gathered on 21 September 1970 from discrete sources in Cygnus are presented. The data from Cyg X-1, Cyg X-2, and Cyg X-3 have sufficient statistical significance to indicate mutually exclusive spectral forms for the three. Upper limits are presented for X-ray intensities above 2 keV for Cyg X-4 and Cyg X-5 (Cygnus loop). A search was made on 9 August 1971 for a diffuse component of X-rays 1.5 keV associated with an interarm region of the galaxy at galactic longitudes in the vicinity of 60 degrees. A statistically significant excess associated with a narrow disk component was detected. Several possible emission models are discussed, with the most likely candidate being a population of unresolvable low luminosity discrete sources.

Bleach, R. D.

1972-01-01

5

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

NASA Technical Reports Server (NTRS)

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).

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

6

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

NASA Astrophysics Data System (ADS)

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

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

2013-04-01

7

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

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.

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

2000-05-01

8

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

E-print Network

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

Su, Xiao

9

The Emission of Cygnus X-1: Observations with INTEGRAL SPI from 20 keV to 2 MeV  

NASA Astrophysics Data System (ADS)

We report on Cyg X-1 observations performed by the SPI telescope on board the INTEGRAL mission and distributed over more than 6 years. We investigate the variability of the intensity and spectral shape of this peculiar source in the hard X-ray domain, and more particularly up to the MeV region. We first study the total averaged spectrum which presents the best signal-to-noise ratio (4 Ms of data). Then, we refine our results by building mean spectra by periods and gathering those of similar hardness. Several spectral shapes are observed with important changes in the curvature between 20 and 200 keV, even at the same luminosity level. In all cases, the emission decreases sharply above 700 keV, with flux values above 1 MeV (or upper limits) well below the recently reported polarized flux, while compatible with the MeV emission detected some years ago by the Compton Gamma-ray Observatory/COMPTEL. Finally, we take advantage of the spectroscopic capability of the instrument to seek for spectral features in the 500 keV region with negative results for any significant annihilation emission on 2 ks and day timescales, as well as in the total data set. Based on observations with INTEGRAL, an ESA project with instruments and science data centre funded by ESA member states (especially the PI countries: Denmark, France, Germany, Italy, Spain, and Switzerland), Czech Republic and Poland with participation of Russia and USA.

Jourdain, E.; Roques, J. P.; Malzac, J.

2012-01-01

10

Angular distribution of bremsstrahlung produced by electrons with initial energies in the range from 10 to 20 keV incident on thick Ag  

NASA Astrophysics Data System (ADS)

Experimental results are presented comparing the intensities of the thick-target bremsstrahlung produced by electrons with initial energies ranging from 10 to 20 keV incident on Ag, measured at forward angles in the range of 0 to 55 degrees. When the data are corrected for attenuation due to photon absorption within the target, the results indicate that the detected radiation is distributed anisotropically only at photon energies k that are approximately equal to the initial energy of the incident electrons E0. The results of our experiments suggest that, as k/E0->0, the detected radiation essentially becomes isotropic due primarily to the scattering of electrons within the target. Comparison to the theory of Kissel et al. [At. Data Nucl. Data Tables 28, 381 (1983)] suggests that the angular distribution of bremsstrahlung emitted by electrons incident on thick targets is similar to the angular distribution of bremsstrahlung emitted by electrons incident on free-atom targets only when k/E0 1. The experimental data also are in approximate agreement with the angular distribution predictions of the Monte Carlo program PENELOPE.

Gonzales, Daniel; Cavness, Brandon; Williams, Scott

2012-03-01

11

Angular distribution of thick-target bremsstrahlung produced by electrons with initial energies ranging from 10 to 20 keV incident on Ag  

NASA Astrophysics Data System (ADS)

Experimental results are presented comparing the intensities of the bremsstrahlung produced by electrons with initial energies ranging from 10 to 20 keV incident on a thick Ag target, measured at forward angles in the range of 0° to 55°. When the data are corrected for attenuation due to photon absorption within the target, the results indicate that the detected radiation is distributed anisotropically only at photon energies k that are approximately equal to the initial energy of the incident electrons E0. The results of our experiments suggest that, as k/E0 ? 0, the detected radiation essentially becomes isotropic due primarily to the scattering of electrons within the target. A comparison to the theory of Kissel [At. Data Nucl. Data TablesADNDAT0092-640X10.1016/0092-640X(83)90001-3 28, 381 (1983)] suggests that the angular distribution of bremsstrahlung emitted by electrons incident on thick targets is similar to the angular distribution of bremsstrahlung emitted by electrons incident on free-atom targets only when k/E0 ? 1. The experimental data also are in approximate agreement with the angular distribution predictions of the Monte Carlo program penelope.

Gonzales, D.; Cavness, B.; Williams, S.

2011-11-01

12

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

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.

Derrien, H

2005-12-05

13

Chain-oxygen ordering in twin-free YBa2Cu3O7-single crystals driven by 20-keV electron irradiation  

E-print Network

Chain-oxygen ordering in twin-free YBa2Cu3O7- single crystals driven by 20-keV electron irradiation 2005 We have examined the effects of 20-keV electron irradiation on the -Cu 1 -O 1 - n chain-oxygen arrange- ments in oxygen-deficient but otherwise twin-free YBa2Cu3O7- single crystals. Comparison

Johansen, Tom Henning

14

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

PubMed

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(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(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.]. PMID:19044569

Bennett, G R; Smith, I C; Shores, J E; Sinars, D B; Robertson, G; Atherton, B W; Jones, M C; Porter, J L

2008-10-01

15

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

NASA Astrophysics Data System (ADS)

When used for the production of an x-ray imaging backlighter source on Sandia National Laboratories' recently upgraded 26MA Z Accelerator, the terawatt-class, multikilojoule, 526.57nm Z-Beamlet laser (ZBL) [P. K. Rambo et al., Appl. Opt. 44, 2421 (2005)], in conjunction with the 6.151keV (1s2-1s2p 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 1mg 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 2-20ns. 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 6.151keV two frame technique has recently been used to image imploding wire arrays, using a 7.3ns 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 6.181keV Mn 1s2-1s2p singlet line), to increase x-ray yields. Also, a highly sensitive inline multiframe ultrafast (1ns 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.

Bennett, G. R.; Smith, I. C.; Shores, J. E.; Sinars, D. B.; Robertson, G.; Atherton, B. W.; Jones, M. C.; Porter, J. L.

2008-10-01

16

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

SciTech Connect

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.].

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

17

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

SciTech Connect

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

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

2013-04-15

18

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

NASA Astrophysics Data System (ADS)

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.

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

2005-07-01

19

The pulse profile of the Crab pulsar in the energy range 45 keV-1.2 MeV  

NASA Technical Reports Server (NTRS)

The Crab Nebula pulsar (PSR 0531+21) is the best studied and most intense of the nontransient X-ray pulsars. However, since its spectrum drops rapidly with energy, a well-resolved pulse profile has not previously been obtained above 200 keV. In the hard X-ray and low-energy gamma-ray region, an accurate pulse profile can be obtained with a balloon-borne detector of sufficient area during a single transit of the source. A new measurement of the pulse profile of PSR 0531+21 in the energy range above 45 keV obtained with a large-area scintillation detector array is reported. The detector array was flown on a balloon launched from Palestine, Texas on 1980 October 6, reaching a float altitude 4.5 g/sq cm at 0230 UTC October 7. The primary objective of the experiment was to detect and study weak gamma-ray bursts.

Wilson, R. B.; Fishman, G. J.

1983-01-01

20

Calculation of electron-impact rotationally elastic total cross sections for NH3, H2S, and PH3 over the energy range from 0.01 eV to 2 keV  

Microsoft Academic Search

This paper report results of calculation of the total cross section QT for electron impact on NH3, H2S, and PH3 over a wide range of incident energies from 0.01 eV to 2 keV. Total cross sections QT (elastic plus electronic excitation) for incident energies below the ionization threshold of the target were calculated using the UK molecular R-matrix code through

Chetan Limbachiya; Minaxi Vinodkumar; Nigel Mason

2011-01-01

21

Electron impact calculations of total elastic cross sections over a wide energy range - 0.01 eV to 2 keV for CH4, SiH4 and H2O  

Microsoft Academic Search

In this paper we report the results of a new theoretical methodology for determining the total elastic electron scattering cross section, Q el , over a wide range of incident energies between 0.01 eV and 2 keV. We have combined results from the UK molecular R-matrix code using Quantemol-N software to determine Q el for incident energies between 0.01 eV

M. Vinodkumar; C. G. Limbachiya; K. N. Joshipura; N. J. Mason

2011-01-01

22

Calculation of electron-impact rotationally elastic total cross sections for NHâ, HâS, and PHâ over the energy range from 0.01 eV to 2 keV  

Microsoft Academic Search

This paper report results of calculation of the total cross section Q{sub T} for electron impact on NHâ, HâS, and PHâ over a wide range of incident energies from 0.01 eV to 2 keV. Total cross sections Q{sub T} (elastic plus electronic excitation) for incident energies below the ionization threshold of the target were calculated using the UK molecular R-matrix

Chetan Limbachiya; Minaxi Vinodkumar; Nigel Mason

2011-01-01

23

Collision spectroscopy of the He/sup 0/ + D/sub 2/ system in the 1 to 2 keV energy range  

SciTech Connect

Direct scattering of He/sup 0/ on D/sub 2/ is studied, both theoretically and experimentally, with particular emphasis on quasi-elastic scattering. Sigmund scaling is demonstrated, despite the presence of inelastic channels. This is significant, because one of the requirements in Sigmund's derivation is that no inelastic channels be open. In addition, cross sections for the quasi-elastic processes as well as the one and two electron excitation processes are studied. Some of the lowest lying excited state surfaces of the HeH/sub 2/ system are calculated, as well as the portion of the ground state surface in which the He projectile is in close proximity to the H/sub 2/ target. Agreement between theory and experiment for the scaling and for the cross sections indicate that some understanding of the ground state energy surface was attained. In addition, classical scattering calculations were carried out to better understand this surface and to understand the breakdown of the scaling due to velocity effects.

Jakacky, J.M. Jr.

1984-01-01

24

Erosion of thin carbon foils by 20 keV and 40 keV Ar{sup +} irradiation  

SciTech Connect

Nominal 2 {mu}g/cm{sup 2} C foils were irradiated with 20 and 40 keV Ar{sup +} ions at fluences up to 1.1x10{sup 16} Ar{sup +}/cm{sup 2}. Foil erosion (determined by measuring changes in angular scatter distribution of 2-keV protons transiting the foil) is observed to reach a constant rate of 3.5 C atoms removed per incident Ar{sup +}. The independence of the sputter yield on foil thickness indicates that interactions leading to sputtering occur within a depth of 0.5 {mu}g/cm{sup 2} of the sputter surface. Using theoretical and TRIM estimates for the backwater sputtering yield, the transmission sputtering yield is a factor of 3-16 times larger than the backward sputtering yield. The fraction of holes created in the foil by Ar{sup +} irradiation linearly increases with fluence above a fluence of 4x10{sup 15} Ar{sup +}/cm{sup 2}, and the foil lifetime is 8.7x10{sup 15} Ar{sup +}/cm{sup 2}.

Funsten, H.O.; Shappirio, M.

1996-10-01

25

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

SciTech Connect

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.

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

1997-11-01

26

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

NASA Astrophysics Data System (ADS)

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).

Valalaki, Katerina; Nassiopoulou, Androula Galiouna

2014-06-01

27

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

PubMed Central

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

2014-01-01

28

Solar Wind ?20–200 keV Superhalo Electrons at Quiet Times  

NASA Astrophysics Data System (ADS)

High-energy superhalo electrons are present in the interplanetary medium (IPM) even in the absence of any significant solar activity, carrying important information on electron acceleration in the solar wind. We present a statistical survey of ?20–200 keV superhalo electrons measured at 1 AU by the WIND 3D Plasma & Energetic Particle instrument during quiet-time periods from 1995 January through 2013 December. The selected 242 quiet-time samples mostly occur during the rising, maximum and decay phases of solar cycles. The observed omnidirectional differential flux of these quiet-time superhalo electrons generally fits to a power-law spectrum J=A× {{(\\frac{E}{{{m}e}{{c}2}})}-? }, with ? ranging from ?1.6 to ?3.7 and the integrated density nsup ranging from 10?8 to 10?5 cm?3. In solar cycle 23 (24), the distribution of ? has a broad maximum between 2.4 and 2.8 (2.0 and 2.4). Both ? and the logarithm of nsup show no obvious correlation with sunspot number, solar flares, solar wind core population, etc. These superhalo electrons may form a quiet-time energetic electron background/reservoir in the IPM. We propose that they may originate from nonthermal processes related to the acceleration of the solar wind such as nanoflares, or could be formed in the IPM due to further acceleration and/or long-distance propagation effects.

Wang, Linghua; Yang, Liu; He, Jiansen; Tu, Chuanyi; Pei, Zhongtian; Wimmer-Schweingruber, Robert F.; Bale, Stuart D.

2015-04-01

29

183W Resonance Parameter Evaluation in the Neutron Energy Range Up to 5 keV  

SciTech Connect

We generated a preliminary set of resonance parameters for {sup 183}W in the neutron energy range of thermal up to 5 keV. In the analyzed energy range, this work represents a significant improvement over the current resonance evaluation in the ENDF/B-VII.1 library limited up to 2.2 keV. The evaluation methodology uses the Reich-Moore approximation to fit, with the R-matrix code SAMMY, the high-resolution measurements performed in 2007 at the GEel LINear Accelerator (GELINA) facility. The transmission data and the capture cross sections calculated with the set of resonance parameters are compared with the experimental values, and the average properties of the resonance parameters are discussed.

Pigni, Marco T [ORNL] [ORNL; Dunn, Michael E [ORNL] [ORNL; Guber, Klaus H [ORNL] [ORNL

2012-01-01

30

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

NASA Technical Reports Server (NTRS)

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.

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

2002-01-01

31

Complex refractive index of ammonium nitrate in the 2-20-?m spectral range  

NASA Astrophysics Data System (ADS)

Using high-resolution Fourier-transform infrared absorbance and transmittance spectral data for ammonium sulfate (AMS), calcium carbonate (CAC), and ammonium nitrate (AMN), we made comparisons with previously published complex refractive-index 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 ?m. Subtractive 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 index obtained for AMN. We performed backscatter calculations using a log-normal size distribution for AMS, AMN, and CAC aerosols to show differences in their backscattered spectra.

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

2003-02-01

32

A Strong Excess in the 20-100 keV Emission of NGC 1365  

NASA Astrophysics Data System (ADS)

We present a new Suzaku observation of the obscured active galactic nucleus in NGC 1365, revealing an unexpected excess of X-rays above 20 keV of at least a factor ~2 with respect to the extrapolation of the best-fitting 3-10 keV model. Additional Swift-BAT and Integral-IBIS observations show that the 20-100 keV is concentrated within ~1.5 arcmin from the center of the galaxy, and is not significantly variable on timescales from days to years. A comparison of this component with the 3-10 keV emission, which is characterized by a rapidly variable absorption, suggests a complex structure of the circumnuclear medium, consisting of at least two distinct components with rather different physical properties, one of which covers >80% of the source with a column density N H ~ 3-4×1024 cm-2. An alternative explanation is the presence of a double active nucleus in the center of NGC 1365.

Risaliti, G.; Braito, V.; Laparola, V.; Bianchi, S.; Elvis, M.; Fabbiano, G.; Maiolino, R.; Matt, G.; Reeves, J.; Salvati, M.; Wang, J.

2009-11-01

33

Charge-coupled-device response to electron beam energies of less than 1 keV up to 20 keV  

NASA Technical Reports Server (NTRS)

Recent developments of backside treatment for the backside-illuminated scientifc CCD imagers have shown near-theoretical efficiency even at the short wavelength region of the spectrum. By using SEM performance comparisons of backside-treated and untreated CCDs to an electron flux varying from 1 to 100 pA and beam energy ranging from less than 1 keV up to 20 keV are obtained. The theoretical analysis, the SEM testing procedure, and the quantum efficiency measurement results are presented. It is shown, for example, that the average quantum efficiency increases from less than 1 percent for an untreated CCD to nearly 40 percent for a backside-treated CCD at a beam energy of 1 kev.

Daud, Taher; Janesick, James R.; Evans, Kenneth; Elliott, Tom

1987-01-01

34

Maskless implants of 20 keV Ga+ in thin crystalline silicon on insulator  

NASA Astrophysics Data System (ADS)

A nano-sized ion beam apparatus has been used as maskless lithography to implant 20 keV Ga+ ions into a 26 nm thick silicon crystalline film on insulator. The ion beam, with about 5 nm standard deviation, delivered few hundred ions during a single shot. Circular areas with nominal diameter of 20 or 50 nm were irradiated to a fluence of 5 × 1014/cm2. Transmission electron microscopy evidenced that the damaged regions are characterized by an irregular contour with many disordered filaments. Damage extends across the layer thickness and fast Fourier transform analysis indicates that implantation causes the amorphization of a region which extends beyond the nominal diameter. In situ annealing experiments demonstrated that the disordered filamentary regions disappear in the 250-450 °C temperature range and the interfaces with the surrounding crystalline regions sharpen. A temperature as high as 600 °C is required to fully re-crystallize the amorphous core of the implanted dots. Reordering occurs by multi-orientation lateral solid-phase epitaxial growth and the breaking of (111) and (101) interfaces, due to the formation of twins, triggers a fast crystallization kinetics. Rapid thermal annealing (890 °C-10 s) completely crystallizes the amorphous regions, twins are absent and small cluster of defects remains instead. Preliminary scanning capacitance measurements indicate that the implanted atoms, after crystallization, are electrically active. The implant method is then a viable processing step for the doping of non-bulk fully depleted ultra-thin-body MOSFET.

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

2013-01-01

35

Measurement of the {sup 237}Np(n,{gamma}) cross section from 20 meV to 500 keV with a high efficiency, highly segmented 4{pi} BaF{sub 2} detector  

SciTech Connect

The {sup 237}Np(n,{gamma}){sup 238}Np cross section has been measured in the neutron energy range from 20 meV to 500 keV using the DANCE array at the Los Alamos National Laboratory. This new facility allows experiments with submilligram samples and is therefore well suited to investigate isotopes with half-lives as low as a few hundred days. In this benchmark measurement, only 0.42 mg of {sup 237}Np was sufficient to determine differential cross sections relative to the well-known resonance at 0.5 eV. The thermal cross section was measured to {sigma}{sub 2200m/s}=177{+-}5 barn, {sigma}{sub kT=25.3meV}=167{+-}4 barn and the resonance integral to RI=693{+-}6 barn.

Esch, E.-I.; Bond, E. M.; Bredeweg, T. A.; Couture, A.; Glover, S. E.; Haight, R. C.; Jandel, M.; Kawano, T.; Mertz, A.; O'Donnell, J. M.; Rundberg, R. S.; Schwantes, J. M.; Ullmann, J. L.; Vieira, D. J.; Wilhelmy, J. B.; Wouters, J. M. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Reifarth, R. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Colorado School of Mines, Golden, Colorado 80401 (United States); Greife, U.; Hatarik, A. M.; Hatarik, R. [Colorado School of Mines, Golden, Colorado 80401 (United States)

2008-03-15

36

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

SciTech Connect

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.

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

37

Maskless implants of 20 keV Ga{sup +} in thin crystalline silicon on insulator  

SciTech Connect

A nano-sized ion beam apparatus has been used as maskless lithography to implant 20 keV Ga{sup +} ions into a 26 nm thick silicon crystalline film on insulator. The ion beam, with about 5 nm standard deviation, delivered few hundred ions during a single shot. Circular areas with nominal diameter of 20 or 50 nm were irradiated to a fluence of 5 Multiplication-Sign 10{sup 14}/cm{sup 2}. Transmission electron microscopy evidenced that the damaged regions are characterized by an irregular contour with many disordered filaments. Damage extends across the layer thickness and fast Fourier transform analysis indicates that implantation causes the amorphization of a region which extends beyond the nominal diameter. In situ annealing experiments demonstrated that the disordered filamentary regions disappear in the 250-450 Degree-Sign C temperature range and the interfaces with the surrounding crystalline regions sharpen. A temperature as high as 600 Degree-Sign C is required to fully re-crystallize the amorphous core of the implanted dots. Reordering occurs by multi-orientation lateral solid-phase epitaxial growth and the breaking of (111) and (101) interfaces, due to the formation of twins, triggers a fast crystallization kinetics. Rapid thermal annealing (890 Degree-Sign C-10 s) completely crystallizes the amorphous regions, twins are absent and small cluster of defects remains instead. Preliminary scanning capacitance measurements indicate that the implanted atoms, after crystallization, are electrically active. The implant method is then a viable processing step for the doping of non-bulk fully depleted ultra-thin-body MOSFET.

Mio, A. M.; D'Arrigo, G.; Rimini, E.; Spinella, C. [IMM-CNR, Strada VIII 5, Zona Industriale, I-95121 Catania (Italy); Milazzo, R. G. [IMM-CNR, Strada VIII 5, Zona Industriale, I-95121 Catania (Italy); Dipartimento di Fisica e Astronomia, Universita di Catania, Via S. Sofia 64, I-95123 Catania (Italy); Peto, L.; Nadzeyka, A.; Bauerdick, S. [Raith GmbH, Konrad-Adenauer-Allee 8, 44263 Dortmund (Germany)

2013-01-28

38

Prediction of the spectrum of atmospheric microburst noise in the range 2-20 Hz - Preliminary results  

NASA Technical Reports Server (NTRS)

An engineering estimate of the spectrum of atmospheric microburst noise radiation in the range 2-20 Hz is developed. This prediction is obtained via a marriage of standard aeroacoustic theory with a numerical computation of the relevant fluid dynamics. The 'computational aeroacoustics' technique applied here to the interpretation of atmospheric noise measurements is illustrative of a methodology that can now be employed in a wide class of problems.

Hardin, Jay C.; Pope, D. Stuart

1989-01-01

39

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

NASA Astrophysics Data System (ADS)

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.

Midgley, S. M.

2013-02-01

40

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

PubMed

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 N(e) and fourth compositional ratio R(4) 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 N(e) and R(4). 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 (?N(e), ?R(4)) are (1.0%, 0.5%) for soft tissue and (1.5%, 0.8%) for bone like samples. PMID:23369847

Midgley, S M

2013-02-21

41

12.2-GHz methanol maser MMB follow-up catalogue - III. Longitude range 10 to 20 degrees  

E-print Network

We present the third instalment of a series of catalogues presenting 12.2-GHz methanol maser observations made towards each of the 6.7-GHz methanol masers detected in the Methanol Multibeam (MMB) Survey. The current portion of the catalogue includes the Galactic longitude region 10 to 20 degrees, where we detect 47 12.2-GHz methanol masers towards 99 6.7-GHz targets. We compare the occurrence of 12.2-GHz methanol masers with water maser emission, for which all 6.7-GHz methanol masers in the 6 to 20 degrees longitude range have now been searched. We suggest that the water masers follow a more complicated evolutionary scenario than has been found for the methanol and OH masers, likely due to their different pumping mechanisms. Comparisons of the 6.7-GHz methanol to OH maser peak flux density ratio and the luminosity of the associated 12.2-GHz sources suggests that the 12.2-GHz maser luminosity begins to decline around the time that an OH maser becomes detectable.

Breen, Shari; Caswell, James; Green, James; Voronkov, Maxim; Avison, Adam; Fuller, Gary; Quinn, Lyshia; Titmarsh, Anita

2013-01-01

42

20 keV Minimum Gap Undulator at 6 GeV Argonne National Laboratory  

E-print Network

of the fundamental wavelength is shown in Fig, 4 as a function of the undulator gap. To achieve the photon energy20 keV Minimum Gap Undulator at 6 GeV s. H. Kim Argonne National Laboratory 1. Introduction LS-7 S period, and g = undulator gap. Typically M = 4, h/A = 1/4 and Br = 0.9 ~ 0.9ST are used for the design u

Kemner, Ken

43

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

SciTech Connect

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.

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

2013-06-13

44

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

NASA Technical Reports Server (NTRS)

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.

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

1990-01-01

45

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

SciTech Connect

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

Wang, C.L.; Leipelt, G.R.; Nilson, D.G.

1984-10-03

46

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

SciTech Connect

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

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

2014-04-21

47

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

NASA Astrophysics Data System (ADS)

The energy dependence of the yields of single and double strand breaks (SSB and DSB) and crosslinks induced by electron impact on plasmid DNA films is measured in the 2-20 eV range. The yield functions exhibit two strong maxima, which are interpreted to result from the formation of core-excited resonances (i.e., transient anions) of the bases, and their decay into the autoionization channel, resulting in ? ? ?* electronic transitions of the bases followed by electron transfer to the C-O ?* bond in the phosphate group. Occupancy of the ?* orbital ruptures the C-O bond of the backbone via dissociative electron attachment, producing a SSB. From a comparison of our results with those of other works, including theoretical calculations and electron-energy-loss spectra of the bases, the 4.6 eV peak in the SSB yield function is attributed to the resonance decay into the lowest electronically excited states of the bases; in particular, those resulting from the transitions 13A' (?2 ? ?3*) and 13A? (n2 ? ?3*) of thymine and 13A' (? ? ?*) of cytosine. The strongest peak at 9.6 eV in the SSB yield function is also associated with electron captured by excited states of the bases, resulting mostly from a multitude of higher-energy ? ? ?* transitions. The DSB yield function exhibits strong maxima at 6.1 and 9.6 eV. The peak at 9.6 eV is probably related to the same resonance manifold as that leading to SSB, but the other at 6.1 eV may be more restricted to decay into the electronic state 13A' (? ? ?*) of cytosine via autoionization. The yield function of crosslinks is dominated by a broad peak extending over the 3.6-11.6 eV range with a sharper one at 17.6 eV. The different line shape of the latter function, compared to that of SSB and DSB, appears to be due to the formation of reactive radical sites in the initial supercoiled configuration of the plasmid, which react with the circular form (i.e., DNA with a SSB) to produce a crosslink.

Luo, Xinglan; Zheng, Yi; Sanche, Léon

2014-04-01

48

Calculation of electron-impact rotationally elastic total cross sections for NH{sub 3}, H{sub 2}S, and PH{sub 3} over the energy range from 0.01 eV to 2 keV  

SciTech Connect

This paper report results of calculation of the total cross section Q{sub T} for electron impact on NH{sub 3}, H{sub 2}S, and PH{sub 3} over a wide range of incident energies from 0.01 eV to 2 keV. Total cross sections Q{sub T} (elastic plus electronic excitation) for incident energies below the ionization threshold of the target were calculated using the UK molecular R-matrix code through the Quantemol-N software package and cross sections at higher energies were derived using the spherical complex optical potential formalism. The two methods are found to give self-consistent values where they overlap. The present results are, in general, found to be in good agreement with previous experimental and theoretical results.

Limbachiya, Chetan [P. S. Science College, Kadi 382 715, Gujarat (India); Vinodkumar, Minaxi [V. P. and R. P. T. P. Science College, Vallabh Vidyanagar 388 120, Gujarat (India); Mason, Nigel [Department of Physics and Astronomy, Open University, Milton Keynes, MK7 6AA (United Kingdom)

2011-04-15

49

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

NASA Astrophysics Data System (ADS)

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.

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

50

Contrasting physics in wire array z pinch sources of 1-20?keV emission on the Z facility  

SciTech Connect

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?×?10{sup 21} ions/cm{sup 3}, 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.

Ampleford, D. J., E-mail: damplef@sandia.gov; 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.; Sygar, W. A.; Savage, M. E.; Moore, J. K.; Focia, R.; Wagoner, T. C.; Killebrew, K. L. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States); and others

2014-05-15

51

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

SciTech Connect

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.

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

52

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

NASA Astrophysics Data System (ADS)

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.

Wu, Ming; Moy, Ken; Kruschwitz, Craig; Rochau, Greg

2014-11-01

53

Growth of Sn whiskers after low temperature implantation of 20 keV He or H  

SciTech Connect

Single crystalline whiskers have been observed to form on thin films (approx.100 nm) of Sn following implantation of 20-keV H or He at temperatures below 15/sup 0/K. Rapid warming prevented the formation of whiskers, indicating that the growth occurs predominatly during the warming, and not during implantation. Samples that had been warmed rapidly did show whisker growth only after several days in air at room temperature. The adhesion of the films to the substrate is remarkably enhanced by the irradiation, as measured by scratch tests. Thicker films produced progressively fewer whiskers, and none were observed on implanted foils, or films of In, Bi, Zn, or Pb. Possible origins of the driving force for whisker growth are discussed. Whiskers grew on Sn films on all of the substrates that were tested: quartz, sapphire, glass, Si, Cu, stainless steel, and NaCl.

Poker, D.B.; Schubert, J.; Alexandrou, A.; Froehlingsdorf, J.; Stritzker, B.

1986-01-01

54

Performance of LAPEX and its spectroscopic capabilities in the 20--300 keV energy band to observe SN1987a  

SciTech Connect

Recent observations of SN1987a both in the 1--10 keV and in the 10--350 keV energy range detected X-ray emission from the source with a very hard spectrum, a power law with ..cap alpha..approx.1.4, and a flux of approx.10 mCrab at 30 keV. We describe the performances of the LAPEX experiment for observation of SN1987a. In the 20--300 keV operative energy band of LAPEX, the following goals can be achieved: detection of emission lines due to Co/sup 57/ (122 keV) and Ti/sup 44/ (67.9 and 78.4 keV), elements that could be produced in the supernova explosion; measurement of the comptonized spectrum from the expanding ejecta; investigation on possible coherent pulsations due to a newly born pulsar down to timescales of approx.0.1 ms. In the following, a thorough description of the payload and of its performances will be given.

Frontera, F.; Basili, A.; Dal Fiume, D.; Franceschini, T.; Landini, G.; Morelli, E.; Pamini, M.; Poulsen, J.M.; SIlvestri, S.; Costa, E.; and others

1988-09-25

55

Spectral Constraints on SEYFERT-2 Galaxies as Major Contributors to the Hard 3-100-KEV X-Ray Background  

NASA Astrophysics Data System (ADS)

It has been suggested that the flat spectrum of the X-ray background (XRB) above 3 keV and below ~15 keV could be explained by the superposition of absorbed sources at different redshifts. To explain the steepening of the XRB spectrum above ~15 keV, the intrinsic source spectrum should cut off at ~50-100 keV, as observed in NGC 4151 and galactic black hole candidates. Here, assuming that Seyfert 2 galaxies are Seyfert 1 galaxies obscured by intervening matter in the line of sight, as postulated by the unified model, and that they provide the major contribution to the XRB in the 3-100 keV energy range, we derive some constraints on their spectrum and evolution, and indicate, in view of future ASCA measurements, the use of iron spectral features as a test of the model.

Matt, G.; Fabian, A. C.

1994-03-01

56

Spectral sensitivity of the Y?-4 photographic film in the 0.27–3keV range  

Microsoft Academic Search

The sensitometric characteristics of a Y?-4 photographic film were measured in the 0.27–3 keV spectral region. It was ascertained\\u000a that, as the photon energy decreased from 3.2 to 1.2 keV, the Y?-4 photographic-film sensitivity remained virtually constant\\u000a and the abruptly fell. Comparison of the Y?-4, Y?-2T and Y?-P films showed that their sensitivities are functions of the photon\\u000a energy.

A. V. Bessarab; S. A. Pospelova; V. A. Tokarev; A. V. Chukalovskii

2000-01-01

57

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)

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.

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

2014-06-01

58

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

E-print Network

We study the spectrum of the cosmic X-ray background (CXB) in energy range $\\sim$5-100 keV. Early in 2006 the INTEGRAL observatory performed a series of four 30ksec observations with the Earth disk crossing the field of view of the instruments. The modulation of the aperture flux due to occultation of extragalactic objects by the Earth disk was used to obtain the spectrum of the Cosmic X-ray Background(CXB). Various sources of contamination were evaluated, including compact sources, Galactic Ridge emission, CXB reflection by the Earth atmosphere, cosmic ray induced emission by the Earth atmosphere and the Earth auroral emission. The spectrum of the cosmic X-ray background in the energy band 5-100 keV is obtained. The shape of the spectrum is consistent with that obtained previously by the HEAO-1 observatory, while the normalization is $\\sim$10% higher. This difference in normalization can (at least partly) be traced to the different assumptions on the absolute flux from the Crab Nebulae. The increase relative to the earlier adopted value of the absolute flux of the CXB near the energy of maximum luminosity (20-50 keV) has direct implications for the energy release of supermassive black holes in the Universe and their growth at the epoch of the CXB origin.

E. Churazov; R. Sunyaev; M. Revnivtsev; S. Sazonov; S. Molkov; S. Grebenev; C. Winkler; A. Parmar; A. Bazzano; M. Falanga; A. Gros; F. Lebrun; L. Natalucci; P. Ubertini; J. -P. Roques; L. Bouchet; E. Jourdain; J. Knoedlseder; R. Diehl; C. Budtz-Jorgensen; S. Brandt; N. Lund; N. J. Westergaard; A. Neronov; M. Turler; M. Chernyakova; R. Walter; N. Produit; N. Mowlavi; J. M. Mas-Hesse; A. Domingo; N. Gehrels; E. Kuulkers; P. Kretschmar; M. Schmidt

2007-02-12

59

Structural studies of Li 0.7VO 2 in the temperature range 20-300°C  

NASA Astrophysics Data System (ADS)

The ordered rock-salt type compound Li 0.7VO 2 has recently been found to exhibit some unusually large hysteresis effects in its magnetic and thermal properties between 150 and 280°C, related to the magnetic transition known to occur at about 190°C in LiVO 2. X-ray and neutron powder diffraction measurements have been made on samples of Li 0.7VO 2 in an effort to classify structural changes believed to accompany this transition but not hitherto reported in any detail. The unit cell parameters were found to change from a = 2.837, c = 14.775 Å at 24°C to a = 2.913, c = 14.640 Å at 263°C, with a large discontinuity in the transition region. Rietveld refinement was carried out on X-ray data collected at these temperatures and on neutron data collected at 35°C, the main change being an increase in the V?O and V?V distances from 1.98 and 2.84 Å at 24°C to 2.02 and 2.91 Å at 263°C, respectively. The only indication of any departure from R overline3m symmetry in the low-temperature phase was the presence of two extremely weak superlattice peaks in the 24°C X-ray data which can be indexed in terms of an enlarged cell with a' = a?3, c' = c. Above 250°C, the gradual development of a second phase was noted, identified as the cubic spinel LiV 2O 4 resulting from the disproportionation of Li 0.7VO 2 into LiVO 2 and the spinel. Hysteresis effects were observed in the X-ray data which closely parallel those previously reported for the magnetic and thermal properties and which can be attributed to the disproportionation reaction.

Cardoso, L. P.; Cox, D. E.; Hewston, T. A.; Chamberland, B. L.

1988-02-01

60

Production and Performance of the InFOCmicronS 20-40 keV Graded Multilayer Mirror  

NASA Technical Reports Server (NTRS)

The International Focusing Optics Collaboration for micron Crab Sensitivity (InFOC micronS) balloon-borne hard x-ray incorporates graded multilayer technology to obtain significant effective area at energies previously inaccessible to x-ray optics. The telescope mirror consists of 2040 segmented thin aluminum foils coated with replicated Pt/C multilayers. A sample of these foils was scanned using a pencil-beam reflectometer to determine, multilayer quality. The results of the reflectometer measurements demonstrate our capability to produce large quantity of foils while maintaining high-quality multilayers with a mean Nevot-Croce interface roughness of 0.5nm. We characterize the performance of the complete InFOC micronS telescope with a pencil beam raster scan to determine the effective area and encircled energy function of the telescope. The effective area of the complete telescope is 78, 42 and 22 square centimeters at 20 30 and 40 keV. respectively. The measured encircled energy fraction of the mirror has a half-power diameter of 2.0 plus or minus 0.5 arcmin (90% confidence). The mirror successfully obtained an image of the accreting black hole Cygnus X-1 during a balloon flight in July, 2001. The successful completion and flight test of this telescope demonstrates that graded-multilayer telescopes can be manufactured with high reliability for future x-ray telescope missions such as Constellation-X.

Berendse, F.; Owens, S. M.; Serlemitsos, P. J.; Tueller, J.; Chan, K.-W.; Soong, Y.; Krimm, H.; Baumgartner, W. H.; Tamura, K.; Okajima, T.; Tawara, Y.; White, Nicholas E. (Technical Monitor)

2002-01-01

61

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

Microsoft Academic Search

Mass attenuation coefficients of some boron compounds (H3BO3,Na2B4O7 and B3Al2O3) and the trommel sieve waste (TSW) have been measured by using an extremely narrow collimated-beam transmission method in the energy range 15.746–40.930keV. The characteristic K? and K? X-rays of Zr, Mo, Ag, In, Sb, Ba and Pr passed through H3BO3,Na2B4O7, B3Al2O3 and TSW were detected with a high-resolution Si(Li) detector.

Orhan ?çelli; Salih Erzeneo?lu; Recep Boncukçuo?lu

2003-01-01

62

Strength of the Ec.m.=1113 keV resonance in 20Ne(p,?)21Na  

NASA Astrophysics Data System (ADS)

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

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

2013-09-01

63

Mechanisms of O2 sputtering from water ice by keV ions  

NASA Astrophysics Data System (ADS)

We have conducted experiments on the sputtering of water ice by 100 keV Ar+ between 20 and 150 K. Our findings indicate that the temperature dependence of the total sputtering yield is heavily influenced by the thermal and irradiation history of the ice, showing a complex dependence on irradiation fluence that is correlated to the ejection of O2 molecules. The results suggest that O2 produced by the ions inside the ice diffuses to the surface where it is trapped and then ejected via sputtering or thermal desorption. A high concentration of O2 can trap in a subsurface layer during bombardment at 130 K, which we relate to the formation of hydrogen and its escape from that region. A simple model allows us to determine the depth profile of the absolute concentration of O2 trapped in the ice.

Teolis, B. D.; Vidal, R. A.; Shi, J.; Baragiola, R. A.

2005-12-01

64

EMISSION LINES BETWEEN 1 AND 2 keV IN COMETARY X-RAY SPECTRA  

SciTech Connect

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.

Ewing, Ian; Christian, Damian J. [Department of Physics and Astronomy, California State University, 18111 Nordhoff Street, Northridge, CA 91330 (United States)] [Department of Physics and Astronomy, California State University, 18111 Nordhoff Street, Northridge, CA 91330 (United States); Bodewits, Dennis [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States)] [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Dennerl, Konrad [Max-Planck-Institut fuer extraterrestrische Physik, Postfach 1312, D-85741 Garching Germany (Germany)] [Max-Planck-Institut fuer extraterrestrische Physik, Postfach 1312, D-85741 Garching Germany (Germany); Lisse, Carey M. [Planetary Exploration Group, Space Department, Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Rd, Laurel, MD 20723 (United States)] [Planetary Exploration Group, Space Department, Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Rd, Laurel, MD 20723 (United States); Wolk, Scott J., E-mail: ian.ewing.794@my.csun.edu, E-mail: daman.christian@csun.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

2013-01-20

65

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 keV-60 keV.  

SciTech Connect

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.

de Jonge, M. D.; Tran, C. Q.; Chantler, C. T.; Barnea, Z.; Dhal, B. P.; Paterson, D.; Kanter, E. P.; Southworth, S. H.; Young, L.; Beno, M. A.; Linton, J. A.; Jennings, G.; Univ. of Melbourne; Australian Synchrotron Project

2007-01-01

66

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

NASA Astrophysics Data System (ADS)

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.

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

2014-12-01

67

Airborne 2 color ranging experiment  

NASA Technical Reports Server (NTRS)

Horizontal variations in the atmospheric refractivity are a limiting error source for many precise laser and radio space geodetic techniques. This experiment was designed to directly measure horizontal variations in atmospheric refractivity, for the first time, by using 2 color laser ranging measurements to an aircraft. The 2 color laser system at the Goddard Optical Research Facility (GORF) ranged to a cooperative laser target package on a T-39 aircraft. Circular patterns which extended from the southern edge of the Washington D.C. Beltway to the southern edge of Baltimore, MD were flown counter clockwise around Greenbelt, MD. Successful acquisition, tracking, and ranging for 21 circular paths were achieved on three flights in August 1992, resulting in over 20,000 two color ranging measurements.

Millar, Pamela S.; Abshire, James B.; Mcgarry, Jan F.; Zagwodzki, Thomas W.; Pacini, Linda K.

1993-01-01

68

The X-ray Emissivity of the Universe: 2-200 Kev  

NASA Technical Reports Server (NTRS)

Observational results on the diffuse X-ray background between 2 and 200 keV are reported. Data are presented as a function of the volume emissivity function B (E) (ergs/sec cu Mpc keV emitted at energy E). The prescription for this is first to establish the spectral intensity I (E) (ergs/sec sq cm ster keV) measured at the earth, second to subtract the contribution due to known, discrete sources, and third to unfold the integral equation which relates the measured intensity to the emissivity.

Schwartz, D.; Gursky, H.

1973-01-01

69

Fracture behavior of a B2 Ni-30Al-20Fe-0.05Zr intermetallic alloy in the temperature range 300 to 1300 K  

NASA Technical Reports Server (NTRS)

The fracture behavior of a B2 Ni-30Al-20Fe-0.05Zr (at. pct) alloy was investigated using results of tensile tests conducted in the temperature range 300-1300 K under initial strain rates that varied between 10 exp -6 and 10 exp -3/sec, together with results of deformation measurements reported by Raj et al. (1992). Microstructural observations revealed that the alloy had failed by transgranular cleavage fracture below 873 K and by ductile fracture, power-law cavitation, triple point cracking, and rupture above this temperautre. The fracture map constructed using fracture results is compared with those for other classes of materials, showing that the atomic bonding plays a significant role in the low-temperature ductility of NiAl-based alloys.

Raj, S. V.

1992-01-01

70

Solar wind control of Earth's H+ and O+ outflow rates in the 15-eV to 33-keV energy range  

NASA Astrophysics Data System (ADS)

Earth's high-latitude outflow of H+ and O+ ions has been examined with the Toroidal Imaging Mass-Angle Spectrograph instrument on the Polar satellite in the 15-eV to 33-keV energy range over an almost 3-year period near solar minimum (1996-1998). This outflow is compared with solar wind plasma and interplanetary magnetic field (IMF) data from the Wind spacecraft, the latter having been time shifted to the subsolar magnetopause and averaged for 15 min prior to each sampling of Earth's magnetic field-aligned ion flow densities. When the flow data are arranged according to the polarity of the IMF Bz (in GSM coordinates) and limited to times with Bz > 3 nT or Bz < -3 nT, the total rate of ion outflow is seen to be significantly enhanced with negative Bz, typically by factors of 2.5-3 for the O+ and 1.5-2 for the H+, more than previously reported from similar but less extensive comparisons. With either IMF Bz polarity the rate of ion outflow is well correlated with the solar wind energy flow density, especially well with the density of kinetic energy flow. The rate of ion outflow within the instrument's energy range is a strong function of the Polar satellite altitude, increasing almost threefold from perigee (R ˜ 2 RE) toward apogee (R ˜ 4-9 RE) for O+ ions, i.e., up to 1026 ions s-1 or more per hemisphere. The apogee enhancement may be still larger for the H+, but it is obscured by mantle flow of cusp origin solar H+. Ion mean energy also increases with altitude, leading to about a twentyfold increase in the O+ energy flow rate from Polar perigee to apogee altitude, reaching values of 20 GW or more per hemisphere. While the perigee outflow of H+ has little or no seasonal modulation, in terms of ions s-1 the O+ outflow rates at both altitudes do increase during local summer and so does the rate of cusp origin H+ flow near apogee. The latter rate, in fact, has very similar seasonal modulation as the O+ rates, suggesting that it has a significant influence on the O+ outflow.

Lennartsson, O. W.; Collin, H. L.; Peterson, W. K.

2004-12-01

71

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

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

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

72

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

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

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

73

Mu-2 ranging  

NASA Technical Reports Server (NTRS)

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.

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

1977-01-01

74

Optimum condition of efficiency functions for HPGe ?-ray detectors in the 121-1408 keV energy range  

NASA Astrophysics Data System (ADS)

The optimum condition of three commonly used functions in the Genie 2000 ? spectra analysis software have been studied in the 121-1408 keV energy range. The three functions are applied for fitting the full-energy peak efficiency of the HPGe gamma-ray detector. A detailed procedure to obtain the optimum condition is described. The HPGe detector is calibrated at 11 cm by three radioactive sources of point form (152Eu, 137Cs, 60Co) providing 11 energy peaks. After data processing, results shows that the three functions used in the Genie 2000 gamma spectra analysis software fit best at orders 3-5. Lastly the standard radioactive source 133Ba is chosen to validate the results. Differences between the standard activity of 133Ba and the result obtained from the fitting functions are below 1.5%. Therefore the optimum orders of the three functions used in the Genie 2000 ? spectra analysis software are 3-5 with the 11 energy peaks.

Chen, Zhi-Lin; Song, Guo-Yang; Mu, Long; Wang, He-Yi; Xing, Shi-Xiong; Guo, Hong-Bo; Liao, Zhen-Xing; Chen, Ping; Hua, Sheng

2010-05-01

75

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

SciTech Connect

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

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

2012-03-01

76

Kirkpatrick-Baez microscope with spherical multilayer mirrors around 2.5keV photon energy  

NASA Astrophysics Data System (ADS)

A Kirkpatrick-Baez (KB) x-ray microscope has been developed for the diagnostics of inertial confinement fusion (ICF). The KB microscope system works around 2.5keV with the magnification of 20. It consists of two spherical multilayer mirrors. The grazing angle is 3.575° at 2.5keV. The influence of the slope error of optical components and the alignment errors is simulated by SHADOW software. The mechanical structure which can perform fine tuning is designed. Experiment result with Manson x-ray source shows that the spatial resolution of the system is about 3-4?m over a field of view of 200?m.

An, Ning; Du, Xuewei; Wang, Qiuping; Cao, Zhurong; Jiang, Shaoen; Ding, Yongkun

2014-09-01

77

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

PubMed

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

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

2015-03-01

78

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

NASA Astrophysics Data System (ADS)

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.

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

2014-10-01

79

Experimental binding energies for the metal complexes [Mg(CH3OH)n](2+), [Ca(CH3OH)n](2+), and [Sr(CH3OH)n](2+) for n in the range 4-20.  

PubMed

A supersonic source of clusters has been used to prepare neutral complexes of methanol in association with an alkaline earth metal atom. From these complexes the following metal-containing dications have been generated through electron ionization: [Mg(CH3OH)n](2+), [Ca(CH3OH)n](2+), and [Sr(CH3OH)n](2+), and for n in the range 4-20, kinetic energy release measurements following the evaporation of a single molecule have been undertaken using a high resolution mass spectrometer. Using finite heat bath theory, these data have been transformed into binding energies for individual methanol molecules attached to each of the three cluster systems. In the larger complexes (n > 6) the results exhibit a consistent trend, whereby the experimental binding energy data for all three metal ions are similar, suggesting that the magnitude of the charge rather than charge density influences the strength of the interaction. From a comparison with data recorded previously for (CH3OH)nH(+) it is found that the 2+ charge on a metal ion has an effect on the binding energy of molecules in complexes containing up to 20 solvent molecules. The results recorded for [Ca(CH3OH)n](2+) show evidence of a very marked transition between n = 6 and 7, which is thought to coincide with the completion of a primary solvation shell and the onset of molecules starting to occupy a second and most probably a third shell. PMID:25231925

Bruzzi, E; Stace, A J

2014-10-01

80

Marketing 2.0  

ERIC Educational Resources Information Center

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)…

Germain, Carol Anne

2008-01-01

81

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

NASA Technical Reports Server (NTRS)

The discovery in XMM-Newton X-ray data of X-ray emission above 2 keY from Jupiter's aurorae has led us to reexamine the Chandra ACIS-S observations taken in Feb 2003. Chandra's superior spatial resolution has revealed that the auroral X-rays with E > 2 keV are emitted from the periphery of the region emitting those with E < 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.

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

2007-01-01

82

An improved long counter for neutron fluence measurement with a flat response over a wide energy range from 1 keV to 15 MeV  

NASA Astrophysics Data System (ADS)

A new long counter has been developed with a flat energy response over a wide range from 1 keV to 15 MeV. It consists of five 3He proportional counter tubes and a number of carefully designed polyethylene moderators. The structure of this detector was determined by careful Monte Carlo simulations. The calculated results show that the efficiency of this counter is uniform from 1 keV neutron energy to 15 MeV. Calibration was performed on an Am-Be source and the accelerator-produced monoenergetic D-D and D-T neutron sources. Fluctuation of the response curve is less than 10% over this energy range.

Hu, Q. Y.; Zhang, J. H.; Zhang, D.; Guo, H. S.; Yang, G. Z.; Li, B. J.; Ye, F.; Si, F. N.; Liu, J.; Fu, Y. C.; Ning, J. M.; Yang, J.; Yang, H. H.; Wang, W. C.

2014-12-01

83

Studies on effective atomic numbers and electron densities of essential amino acids in the energy range 1 keV–100 GeV  

Microsoft Academic Search

The effective atomic numbers and electron densities of essential amino acids histidine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine have been calculated for total and partial photon interactions by the direct method in the wide energy range of 1keV–100GeV using WinXCOM. The values of these parameters have been found to change with energy and composition of the amino acids.

S. R. Manohara; S. M. Hanagodimath

2007-01-01

84

Web 2.0, Meet Literacy 2.0  

ERIC Educational Resources Information Center

In this article, Literacy 2.0 is defined in terms of Web 2.0 influences. Literacy 2.0 encompasses several major characteristics that distinguish it from traditional literacy practices (Literacy 1.0). For educational technology professionals, Literacy 2.0 skills become a critical means for developing lifelong learning.

Penrod, Diane

2008-01-01

85

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.

86

On the vectorial photoelectric effect at 2.69 keV  

NASA Technical Reports Server (NTRS)

Recent experiments conducted to study the vectorial photoelectric effect with CsI, Al2O3 and Si photocathodes at 2.69 keV indicate null results. Detailed analysis shows that previously measured modulation can be well explained by geometrical misalignment and a combination of the asymmetric shape of the incident X-ray beam and a small detection area of the photoelectron detector. After the elimination of the sources of spurious modulation, we observed a modulation factor of less than 3 percent for a grazing incidence angle as small as 5 deg. There is no observable difference in the pulse height distribution between s and p states.

Shaw, P. S.; Hanany, S.; Liu, Y.; Church, E. D.; Fleischman, J.; Kaaret, P.; Novick, R.; Santangelo, A.

1991-01-01

87

Biosimilars 2.0  

PubMed Central

In the European Union, biosimilar products have been approved since 2006 under an abbreviated pathway that leverages their similarity to an existing “reference” biological product. The products approved to date are based on recombinant versions of endogenous proteins with well-understood structures and pharmacology, but complicated safety and immunogenicity profiles. The period during the 2000s that included the first reviews, approvals, sale and use of biosimilars is referred to herein as “Biosimilars 1.0.” Over the next several years, a new and advanced tranche of biosimilars will be developed for complex reference products, including medicines used in the treatment of cancer and autoimmune diseases. A global market for biosimilars is developing and this may well foreshadow the beginning of the second era of product development. This Biosimilars 2.0 period will likely be characterized by the development of complex products, global harmonization of standards and the increasing demand for long-term monitoring of pharmaceuticals. The products developed in this period should exhibit high levels of fidelity to the reference products and should be rigorously evaluated in analytical, non-clinical and clinical comparisons. Additionally, Biosimilars 2.0 manufacturers should strive for transparency in their labels and take proactive strides to be accountable to providers and patients for the quality of their products. An important opportunity now exists for the healthcare community, industry and regulators to work in partnership, to outline the appropriate standards for these products and to facilitate increased access while meeting patients' needs. PMID:21512318

Miletich, Joseph; Grampp, Gustavo; Mounho, Barbara

2011-01-01

88

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

NASA Astrophysics Data System (ADS)

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

Wang, En-Liang; Shen, Zhen-Jie; Yang, Hong-Jiang; Tang, Ya-Guo; Shan, Xu; Chen, Xiang-Jun

2014-11-01

89

Energy loss and angular dispersion of 2-200 keV protons in amorphous silicon  

NASA Astrophysics Data System (ADS)

The energy loss of 2-200 keV protons in thin amorphous silicon foils has been measured for projectiles transmitted in the forward direction and as a function of the exit angle. At the lowest energies, differences of up to 30% with recently published values are observed. Angular effects in the energy loss, at low and high energies, have been investigated. The low-energy results are reproduced by model calculations and Monte Carlo simulations, which indicate that the inelastic energy loss does not show a dependence upon the impact parameter in the low energy region. A fitting formula for the present energy loss values is provided.

Famá, M.; Lantschner, G. H.; Eckardt, J. C.; Arista, N. R.; Gayone, J. E.; Sanchez, E.; Lovey, F.

2002-06-01

90

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

NASA Astrophysics Data System (ADS)

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.

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

2012-11-01

91

Structure of Ba(Y(1/2)(+3)Ta(1/2)(+5))03 and its dielecrtric properties in the range 10(exp 2) to 10(exp 14) Hz, 20-600 K  

NASA Astrophysics Data System (ADS)

The goal of this work was to understand the correlation between microscopic material parameters and the dielectric function of candidate materials for applications in the microwave frequency range. The structure and dielectric properties of Ba(2+)(Y(1/2)(3+)Ta(1/2)(5+))03 (BYT), a typical representative of the Ba(B(1/2)(3+)B(1/2)(5+))03 complex perovskite family, has been investigated from 10(exp 2) to 10(exp 14) Hz and from 20 to 600 K. At T(sub c) = 253 +/- 1 K, BYT undergoes an equitranslational improper ferroelastic, second-order phase transition, characterized by the tilting of the oxygen octahedra. The space group symmetry changes from Fm(3-bar)m, in the high temperature phase, to I4/m below T(sub c). The existence of an intermediate temperature region ((T(sub c) - 40) less than T less than T(sub c)) has been observed, where the compound exhibits structural and dielectric properties different from those in the well-defined high (T greater than T(sub c)) and low (T less than (T(sub c) - 40) K) temperature phases. Infrared reflectivity (10(exp 12) to 10(exp 14) Hz) and submillimeter transmission (10(exp 11) to 3 x 10(exp 12) Hz) measurements yield dielectric losses which are believed to be mainly of intrinsic origin (one- and two-phonon absorption). Comparing a theory of two-phonon difference absorption processes, due to thermally activated polar branches, with the loss measured at 400-1400 GHz, the intrinsic loss can be extrapolated to lower frequencies. At 10 GHz the extrapolated value is about 1/4 of the loss actually measured in a BYT resonator. The temperature dependencies indicate the soft branch to be of considerable importance for intrinsic losses. Oxygen vacancies can be excluded as an extrinsic loss source, as sintering and annealing in N2, air, and O2 had no measurable influence on the loss at 10 GHz.

Zurmuehlen, R.; Colla, E.; Dube, D. C.; Petzelt, J.; Reaney, I.; Bell, A.; Setter, N.

1994-11-01

92

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

NASA Technical Reports Server (NTRS)

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

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

1975-01-01

93

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)

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.

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

1997-01-01

94

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.

95

City 2.0  

NSDL National Science Digital Library

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.

2012-01-01

96

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

E-print Network

Finite-Hilbert-basis-set calculations for the angular distribution of ionized electrons produced in p+H impact at 20 keV John F. Reading,* Jun Fu, and Mathew J. Fitzpatrick Center for Theoretical Physics, Physics Department, Texas A&M University... ionization where the electron is ejected into a continuum state; ionization also occurs through charge transfer where the electron is captured onto a bound state of the projectile proton. The cited work notwithstanding, we report here a different way...

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

2004-01-01

97

5-20 keV laser-induced x-ray generation at 1 kHz from a liquid-jet target  

Microsoft Academic Search

We report ultrashort pulse, 1 kHz repetition rate x-ray generation in the 5-20 keV spectral region, induced by the interaction of laser radiation with copper nitrate solution and ethylene glycol liquid-jet targets. The characteristics of the copper nitrate source are relevant for application to time-resolved x-ray diffraction studies as well as for spectroscopic x-ray absorption studies. The x-ray sources were

R. J. Tompkins; I. P. Mercer; M. Fettweis; C. J. Barnett; D. R. Klug; Lord G. Porter; I. Clark; S. Jackson; P. Matousek; A. W. Parker; M. Towrie

1998-01-01

98

Study of natMg(d,d0) reaction at detector angles between 90° and 170°, for the energy range Ed,lab=1660-1990 keV  

NASA Astrophysics Data System (ADS)

In the present work, the study of the natMg(d,d0) is presented for the energy range Ed,lab = 1660-1990 keV (in steps of 5 keV), for detector angles between 90° and 170°. Elastic scattering data for two forward angles (55° and 70°) were also obtained. In order to validate the obtained experimental results a thick Mg sample with Au evaporated on top was fabricated and benchmarking measurements were performed at various deuteron beam energies. The results of the present work are complementary to the recently published 24Mg(d,p0,1,2) reaction cross section data, thus facilitating the simultaneous depth profiling study of magnesium by both the d-NRA and EBS techniques.

Patronis, N.; Aslanoglou, X.; Axiotis, M.; Georgiadou, A.; Kokkoris, M.; Lagoyannis, A.; Misaelides, P.; Paneta, V.

2014-10-01

99

Logue and Singer, HVAC&R, 20(2): 264-275, 2014. Energy Impacts of Effective Residential Range Hood Use, LBNL-6683E Page 1  

E-print Network

was provided by the U.S. Dept. of Energy Building America Program, Office of Energy Efficiency and Renewable the energy demand of the U.S. housing stock. This paper describes a modeling study to determine site energy, source energy, and consumer costs for comprehensive range hood use. To estimate the energy impacts

100

The production and sputtering of S2 by keV ion bombardment  

NASA Technical Reports Server (NTRS)

The ion bombardment of S-containing molecules in comets is simulated experimentally. Mass-analyzed 30-keV beams of Ar(+) and He(+) are directed at solid S, H2S, and CS2 targets at temperatures 15 K, and the neutral molecular species produced are ionized and analyzed using a quadrupole mass spectrometer. The dominant species detected are S1 and S2 for the S target, H2S and S2 for the H2S target, and S, CS, S2, and CS2 for the CS2 target. In the latter case, it is found that after about 10 to the 14th He(+) ions/sq cm have struck the target, further sputtering is prevented by formation of a dark brown deposit which is stable at room temperature; the residue forms more slowly when Ar(+) ions are used. These results, indicating relatively efficient S2 production by ion bombardment, are applied to theoretical models of S2 production and/or ejection by solar-wind, solar-flare, or cosmic-ray ions striking comets. It is found that direct solar-wind production of S2 by sputtering is unlikely at realistic bombardment rates, but that H2S-S2 conversion by energetic ions could be significant, with less stringent ice-temperature and irradiation-flux constraints than in the case of S2 production by photons.

Boring, J. W.; Chrisey, D. B.; Oshaughnessy, D. J.; Phipps, J. A.; Zhao, N.

1986-01-01

101

http://www.sedimentaryores.net/Cascades/MtStHelens/Cascade%20Range%20Lahars.pdf Cascade Range Lahars (Volcanic Debris Flows) JB Maynard 2010  

E-print Network

http://www.sedimentaryores.net/Cascades/MtStHelens/Cascade%20Range%20Lahars.pdf Cascade Range mm to 1m; matrix MtStHelens/Cascade%20Range%20 River, Mt Rainier Jigsaw puzzle clast in S Fork Toutle drainage, Mt St Helens Debris avalanches

Maynard, J. Barry

102

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

SciTech Connect

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.

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

103

CASPER Version 2.0  

NASA Technical Reports Server (NTRS)

CASPER is designed to perform automated planning of interdependent activities within a system subject to requirements, constraints, and limitations on resources. In contradistinction to the traditional concept of batch planning followed by execution, CASPER implements a concept of continuous planning and replanning in response to unanticipated changes (including failures), integrated with execution. Improvements over other, similar software that have been incorporated into CASPER version 2.0 include an enhanced executable interface to facilitate integration with a wide range of execution software systems and supporting software libraries; features to support execution while reasoning about urgency, importance, and impending deadlines; features that enable accommodation to a wide range of computing environments that include various central processing units and random- access-memory capacities; and improved generic time-server and time-control features.

Chien, Steve; Rabideau, Gregg; Tran, Daniel; Knight, Russell; Chouinard, Caroline; Estlin, Tara; Gaines, Daniel; Clement, Bradley; Barrett, Anthony

2007-01-01

104

Xenopatients 2.0  

PubMed Central

In the science-fiction thriller film Minority Report, a specialized police department called “PreCrime” apprehends criminals identified in advance based on foreknowledge provided by 3 genetically altered humans called “PreCogs”. We propose that Yamanaka stem cell technology can be similarly used to (epi)genetically reprogram tumor cells obtained directly from cancer patients and create self-evolving personalized translational platforms to foresee the evolutionary trajectory of individual tumors. This strategy yields a large stem cell population and captures the cancer genome of an affected individual, i.e., the PreCog-induced pluripotent stem (iPS) cancer cells, which are immediately available for experimental manipulation, including pharmacological screening for personalized “stemotoxic” cancer drugs. The PreCog-iPS cancer cells will re-differentiate upon orthotopic injection into the corresponding target tissues of immunodeficient mice (i.e., the PreCrime-iPS mouse avatars), and this in vivo model will run through specific cancer stages to directly explore their biological properties for drug screening, diagnosis, and personalized treatment in individual patients. The PreCog/PreCrime-iPS approach can perform sets of comparisons to directly observe changes in the cancer-iPS cell line vs. a normal iPS cell line derived from the same human genetic background. Genome editing of PreCog-iPS cells could create translational platforms to directly investigate the link between genomic expression changes and cellular malignization that is largely free from genetic and epigenetic noise and provide proof-of-principle evidence for cutting-edge “chromosome therapies” aimed against cancer aneuploidy. We might infer the epigenetic marks that correct the tumorigenic nature of the reprogrammed cancer cell population and normalize the malignant phenotype in vivo. Genetically engineered models of conditionally reprogrammable mice to transiently express the Yamanaka stemness factors following the activation of phenotypic copies of specific cancer diseases might crucially evaluate a “reprogramming cure” for cancer. A new era of xenopatients 2.0 generated via nuclear reprogramming of the epigenetic landscapes of patient-derived cancer genomes might revolutionize the current personalized translational platforms in cancer research. PMID:24406535

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

2014-01-01

105

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

E-print Network

cycle either as a high yield fission product or in alloyed form with applications in reactor piping, fuel cladding, and most importantly as an advanced nuclear fuel in the form of U-Mo [2, 3-mass, light-tight aluminum casing with inner reflective surfaces. Fast-timing modular electronics were

Danon, Yaron

106

Calibration of X-ray detectors in the 8 to 115 keV energy range and their application to diagnostics on the National Ignition Facility  

SciTech Connect

The calibration of X-ray diagnostics is of paramount importance to the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL). National Security Technologies LLC (NSTec) fills this need by providing a wide variety of calibration and diagnostic development services in support of the ongoing research efforts at NIF. The X-ray source in the High Energy X-ray lab utilizes induced fluorescence in a variety of metal foils to produce a beam of characteristic X rays ranging from 8 to 111 keV. Presented are the methods used for calibrating a High Purity Germanium detector, which has been absolutely calibrated using radioactive check sources, compared against a silicon photodiode calibrated at Physikalisch Technische Bundesanstalt (PTB). Also included is a limited presentation of results from the recent calibration of the upgraded Filter Fluorescer X ray Spectrometer.

J. J. Lee, M. J. Haugh, G. LaCaille, and P. Torres

2012-10-01

107

Measurement of the 20 and 90 keV Resonances in the {sup 18}O(p,{alpha}){sup 15}N Reaction via the Trojan Horse Method  

SciTech Connect

The {sup 18}O(p,{alpha}){sup 15}N 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 {sup 18}O(p,{alpha}){sup 15}N 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.

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.; Tumino, A. [INFN Laboratori Nazionali del Sud and DMFCI Universita di Catania, 95123 Catania (Italy); Mukhamedzhanov, A. M.; Tribble, R. E.; Banu, A.; Goldberg, V. Z.; Tabacaru, G.; Trache, L. [Cyclotron Institute, Texas A and M University, College Station, 77843 Texas (United States); Irgaziev, B. [GIK Institute of Engineering Sciences and Technology, Topi (23640), NWFP Pakistan (Pakistan); Coc, A. [CSNSM, CNRS/IN2P3 Universite Paris Sud, F-91405 Orsay (France)] (and others)

2008-10-10

108

An Electrically Driven Terahertz Modulator with over 20 dB of Dynamic Range  

E-print Network

O-2 An Electrically Driven Terahertz Modulator with over 20 dB of Dynamic Range N in ordinary materials. Of particular interest in the terahertz range are planar metamaterials that can be electrically switched. This provides a method for high- speed modulation of terahertz radiation, a goal

109

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

SciTech Connect

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.

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

2010-06-23

110

Understanding Web 2.0  

Microsoft Academic Search

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

San Murugesan

2007-01-01

111

ART: Surveying the Local Universe at 2-11 keV  

NASA Technical Reports Server (NTRS)

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.

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

112

Medical Librarian 2.0  

Microsoft Academic Search

Web 2.0 refers to an emerging social environment that uses various tools to create, aggregate, and share dynamic content in ways that are more creative and interactive than transactions previously conducted on the Internet. The extension of this social environment to libraries, sometimes called Library 2.0, has profound implications for how librarians will work, collaborate, and deliver content. Medical librarians

Elizabeth Connor

2007-01-01

113

Library Instruction 2.0  

ERIC Educational Resources Information Center

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…

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

2009-01-01

114

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

NASA Astrophysics Data System (ADS)

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!

Abram, S.

2007-10-01

115

Learning to Apply Metrology Principles to the Measurement of X-ray Intensities in the 500 eV to 110 keV Energy Range  

SciTech Connect

National Security Technologies, LLC (NSTec), Livermore Operations, has two optical radiation calibration laboratories accredited by “the National Voluntary Laboratories Accreditation Program (NVLAP) which is the accrediting body of” the National Institute of Standards and Technology (NIST), and is now working towards accreditation for its X-ray laboratories. NSTec operates several laboratories with X-ray sources that generate X-rays in the energy range from 50 eV to 115 keV. These X-ray sources are used to characterize and calibrate diagnostics and diagnostic components used by the various national laboratories, particularly for plasma analysis on the Lawrence Livermore National Laboratory (LLNL) National Ignition Facility (NIF). Because X-ray photon flux measurement methods that can be accredited, i.e., traceable to NIST, have not been developed for sources operating in these energy ranges, NSTec, NIST, and the National Voluntary Accreditation Program (NVLAP) together have defined a path toward the development and validation of accredited metrology methods for X-ray energies. The methodology developed for the high energy X-ray (HEX) Laboratory was NSTec’s starting point for X-ray metrology accreditation and will be the basis for the accredited processes in the other X-ray laboratories. This paper will serve as a teaching tool, by way of this example using the NSTec X-ray sources, for the process and methods used in developing an accredited traceable metrology.

Haugh, M. J.; Pond, T.; Silbernagel, C.; Torres, P.; Marlett, K.; Goldin, F.; Cyr, S.

2011-02-08

116

-/20-2-2009 -/20-2-2009  

E-print Network

;-/20-2-2009 µ µ µ Sample Detector Shield Collimated transmission source shieldHPGe Detector 210 240 270 300 10 4 10 5 10 6 10 7 N H N pulses/channel Energy (MeV) 9000 10500 10 2 0.48Boron 2.22Hydrogen 6

117

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

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.

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

118

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)

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.

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

2013-12-01

119

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

SciTech Connect

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.

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

120

Academic Leadership 2.0  

ERIC Educational Resources Information Center

Academic Leadership 2.0 means making an administrative partnership with the faculty the cornerstone of an institution's culture. Administrators have to stop thinking of themselves as operating on a different level from the faculty. The fear many administrators have is that if they demonstrate their willingness to advocate for the faculty, the…

Buller, Jeffrey L.

2013-01-01

121

iPodder 2.0  

NSDL National Science Digital Library

Streaming audio programs on the Web are of great interest to many, and range from those programs sponsored by various policy institutes to popular music programs. Unfortunately, sometimes individuals cannot be present when their favorite programs are broadcast over the Internet. Stepping in to assist users is iPodder 2.0, which allows them to select and download audio files from anywhere on the Internet to their desktops. Also, users can use the application to download various audio files at specific times as well. iPodder 2.0 is compatible with Windows 2000 or XP and Mac OS 10.3 or newer.

122

Revisiting the relationship between 6 ?m and 2-10 keV continuum luminosities of AGN  

NASA Astrophysics Data System (ADS)

We have determined the relation between the AGN luminosities at rest-frame 6 ?m associated with the dusty torus emission and at 2-10 keV energies using a complete, X-ray-flux-limited sample of 232 AGN drawn from the Bright Ultra-hard XMM-Newton Survey. The objects have intrinsic X-ray luminosities between 1042 and 1046 erg s-1 and redshifts from 0.05 to 2.8. The rest-frame 6 ?m luminosities were computed using data from the Wide-field Infrared Survey Explorer and are based on a spectral energy distribution decomposition into AGN and galaxy emission. The best-fitting relationship for the full sample is consistent with being linear, L6 ?m ? L_{2-10 keV}^{0.99± 0.03}, with intrinsic scatter, ? log L6 ?m ˜ 0.35 dex. The L_{6 ? m}/L_{2-10 keV} luminosity ratio is largely independent of the line-of-sight X-ray absorption. Assuming a constant X-ray bolometric correction, the fraction of AGN bolometric luminosity reprocessed in the mid-IR decreases weakly, if at all, with the AGN luminosity, a finding at odds with simple receding torus models. Type 2 AGN have redder mid-IR continua at rest-frame wavelengths <12 ?m and are overall ˜1.3-2 times fainter at 6 ?m than type 1 AGN at a given X-ray luminosity. Regardless of whether type 1 and type 2 AGN have the same or different nuclear dusty toroidal structures, our results imply that the AGN emission at rest-frame 6 ?m is not isotropic due to self-absorption in the dusty torus, as predicted by AGN torus models. Thus, AGN surveys at rest-frame ˜6 ?m are subject to modest dust obscuration biases.

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

2015-05-01

123

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

PubMed

In this work, we present new experimental electron energy loss distribution functions for pyrimidine (C4H4N2) measured for the incident energy range 30-2000 eV. Theoretical total and elastic cross sections for electron scattering from pyrimidine were calculated using the screening-corrected additivity rule (IAM-SCAR) method. Based on the mean energy loss observed in the experiment and the theoretical integral inelastic cross section, the stopping power for electrons in pyrimidine is calculated in the energy range 20-3000 eV. PMID:23415108

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

2014-01-01

124

Autogen Version 2.0  

NASA Technical Reports Server (NTRS)

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.

Gladden, Roy

2007-01-01

125

Introducing Science 2.0!  

ERIC Educational Resources Information Center

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

Brunsell, Eric; Horejsi, Martin

2010-01-01

126

7 CFR 20.2 - Administration.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Administration. 20.2 Section 20.2 Agriculture Office of the Secretary of Agriculture EXPORT SALES REPORTING REQUIREMENTS § 20.2 Administration. The regulations of this...

2010-01-01

127

30 CFR 20.2 - Definitions.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Definitions. 20.2 Section 20.2 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION...ELECTRIC MINE LAMPS OTHER THAN STANDARD CAP LAMPS § 20.2 Definitions. (a) Adequate....

2010-07-01

128

28 CFR 20.2 - Authority.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Authority. 20.2 Section 20.2 Judicial Administration DEPARTMENT OF JUSTICE CRIMINAL JUSTICE INFORMATION SYSTEMS General Provisions § 20.2 Authority. These regulations are issued...

2011-07-01

129

28 CFR 20.2 - Authority.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Authority. 20.2 Section 20.2 Judicial Administration DEPARTMENT OF JUSTICE CRIMINAL JUSTICE INFORMATION SYSTEMS General Provisions § 20.2 Authority. These regulations are issued...

2013-07-01

130

28 CFR 20.2 - Authority.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 2014-07-01 false Authority. 20.2 Section 20.2 Judicial Administration DEPARTMENT OF JUSTICE CRIMINAL JUSTICE INFORMATION SYSTEMS General Provisions § 20.2 Authority. These regulations are issued...

2014-07-01

131

28 CFR 20.2 - Authority.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Authority. 20.2 Section 20.2 Judicial Administration DEPARTMENT OF JUSTICE CRIMINAL JUSTICE INFORMATION SYSTEMS General Provisions § 20.2 Authority. These regulations are issued...

2010-07-01

132

28 CFR 20.2 - Authority.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Authority. 20.2 Section 20.2 Judicial Administration DEPARTMENT OF JUSTICE CRIMINAL JUSTICE INFORMATION SYSTEMS General Provisions § 20.2 Authority. These regulations are issued...

2012-07-01

133

Room temperature transparent ferromagnetism in 200 keV Ni2+ ion implanted pulsed laser deposition grown ZnO/sapphire film  

NASA Astrophysics Data System (ADS)

Intrinsic ferromagnetism at room temperature has been observed in ZnO/sapphire films by implantation of 200 keV Ni2+ ions with fluences 6×1015, 8×1015, 1×1016, and 2×1016 ions/cm2. Crystalline phases are identified by glancing angle x-ray diffraction, which shows no extra phase in the implanted films. Highest saturation magnetization (Ms) is observed in the film implanted with the fluence of 8×1015 ions/cm2 as examined by superconducting quantum interference device magnetometry. This film has almost 80% transmittance across visible wavelength range and hence a potential candidate of transparent ferromagnetic semiconductor. Defectlike oxygen vacancies in the films are studied by x-ray photoelectron spectroscopy. Ferromagnetism of the films is explained on the basis of bound magnetic polaron model.

Pandey, B.; Ghosh, S.; Srivastava, P.; Kumar, P.; Kanjilal, D.; Zhou, S.; Schmidt, H.

2010-01-01

134

Spectral reflectance change and luminescence of selected salts during 2-10 KeV proton bombardment - Implications for Io  

NASA Technical Reports Server (NTRS)

Radiation damage and luminescence caused by magnetospheric charged particles have been suggested by several investigators as mechanisms that are capable of explaining some of the peculiar spectral/albedo features of Io. In the present paper, this possibility is pursued by measuring the UV-visual spectral reflectance and luminescent efficiency of several proposed Io surface constituents during 2 to 10 keV proton irradiation at room and low temperatures. The luminescence efficiencies of pure samples, studied in the laboratory, suggest that charged-particle induced luminescence from Io's surface might be observable by spacecraft such as Voyager when viewing Io's dark side.

Nelson, R. M.; Nash, D. B.

1979-01-01

135

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

E-print Network

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

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

2015-01-01

136

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

PubMed

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

Trunova, Valentina; Sidorina, Anna; Kriventsov, Vladimir

2014-10-17

137

The structure and dynamics of the radiation belts from 10 keV to 2 MeV  

NASA Astrophysics Data System (ADS)

The Van Allen Probes mission measures the Earth’s radiation belts with very high spatial, temporal, and energy resolution. Recent analysis has taken advantage of the capability of the ECT/MagEIS instrument’s ability to directly measure penetrating background radiation contributions to the electron count rates - and subtract it - providing spectral measurements that are essentially free of background contamination [Claudepierre et al., 2014]. The “background-subtracted” measurements show a surprising lack of MeV electrons in inner zone of the radiation belt [Fennell et al., 2014]. However at energies below ~1 MeV electrons can be injected through the slot region into the inner belt.Our analysis of these deep particle injections shows (1) there is great variability in the location of the inner edge of the outer zone - both from one event to another and from one energy to another, (2) lower energy electrons (e.g. <300 keV) are injected into the inner zone (e.g. L<2) more often than higher energy electrons (3) electrons with energies as low as 50 keV are frequently injected into the inner zone. We discuss the implications of these new observations for our understanding of radiation belt acceleration and transport.

Reeves, Geoffrey D.; Larsen, Brian A.; Friedel, Reiner H. W.; Claudepierre, Seth G.; Fennell, Joseph F.; Spence, Harlan E.; Turner, Drew L.

2015-04-01

138

Analysis of photon emission from 50--350-keV proton impact on H{sub 2}O  

SciTech Connect

We have measured photon emission cross sections from neutral fragments produced by collisions of 50-350 keV protons with H{sub 2}O molecules. Balmer {alpha}-{delta} emissions from both the target and projectile were recorded. We also analyzed A {sup 2}{Sigma}{sup +}-X {sup 2}{Pi} (0,0) and (1,0) emission from the excited OH fragment produced during target dissociation. Trends in the cross sections revealed two key properties of the collision process: (1) The Bethe theory accurately describes target emission from both H and OH fragments and (2) the ratio of any two Balmer emission cross sections for both the target and projectile can be approximated by simple functions of the respective optical oscillator strengths. Finally, we provide the Bethe fit parameters necessary to calculate the target emission cross sections at all nonrelativistic impact energies.

Goldman, Benjamin D.; Timpone, Stephanie A.; Monce, Michael N.; Mitchell, Laurel; Griffin, Brian [Daghlian Accelerator Laboratory, Department of Physics, Astronomy, and Geophysics, Connecticut College, New London, Connecticut 06320 (United States)

2011-04-15

139

Art Education 2.0  

NSDL National Science Digital Library

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.

Roland, Craig

140

He/sup 0/ on D/sub 2/ collisions at keV energies and the HeH/sub 2/ energy surface  

SciTech Connect

An experimental and theoretical study of He/sup 0/ on D/sub 2/ collisions at energies 1.0, 1.5, and 2.0 keV has been carried out to probe and to understand the energy surface of the ground electronic state of the HeH/sub 2/ triatomic molecule and of the intersections of this surface with those of low-lying electronically excited states. At each collision energy, doubly differential energy-loss spectra have been obtained and the results have been analyzed in terms of a parametric fit to an ab initio calculated ground-state energy surface. The scaled energy loss for quasielastic collisions (electronically elastic collisions with vibrational-rotational excitation) are shown to constitute a sensitive probe of the region of the ground-state energy surface in which the proximity of the He projectile breaks the H/sub 2/ (or D/sub 2/) bond. Sigmund scaling has been experimentally demonstrated to hold for the quasielastic channel in He on D/sub 2/ collisions despite the strong presence of electronically inelastic processes, a finding of particular significance, since the scaling law was derived under the assumption that there are no accessible electronically inelastic channels in the collision system. The theoretical study confirms this behavior for collisions in which electronic excitation is velocity independent and occurs in well-defined surface intersection regions. Cross sections differential in angle but integrated over all vibrotational-rotational inelastic energy losses have been both calculated and experimentally measured for the quasielastic channel, and the two are found to be in good agreement.

Jakacky J. Jr.; Pollack, E.; Snyder, R.; Russek, A.

1985-04-01

141

The PLATO 2.0 mission  

NASA Astrophysics Data System (ADS)

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.

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.; Ammer-von Eiff, M.; 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.; Oliveira Fialho, F. de; 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.

2014-09-01

142

The PLATO 2.0 mission  

NASA Astrophysics Data System (ADS)

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.

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

143

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

SciTech Connect

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.

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

144

Validation Results for LEWICE 2.0  

NASA Technical Reports Server (NTRS)

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%.

Wright, William B.; Rutkowski, Adam

1999-01-01

145

NeXT (New Exploration X-ray Telescope) 10-80 keV0.3-300  

E-print Network

: SXS x1 XX: SXI x1 XX: HXI x2 : SGD x1 NeXTNeXT-SXS He-like ISAS/JAXA NASA NeXT-SXS z ~ 1 IIXT () NeXT 1E10 1E15 1E20 1E25 [Hz] HXI keV MeV SGD NeXT SXI SXS NeXT M82 TeVHESS XDark Particle. of WisconsinMITNASA/GSFCSLAC 550 cm (6 keV) 0.3-10 keV 10 eV(7 keV) (SGD) 120 cm2 () (100 keV) 15 cm2

Enomoto, Ryoji

146

Introducing ADS 2.0  

NASA Astrophysics Data System (ADS)

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

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

2014-01-01

147

WMS Server 2.0  

NASA Technical Reports Server (NTRS)

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

Plesea, Lucian; Wood, James F.

2012-01-01

148

Optimization of phosphor screens for charge coupled device based detectors and 7-34 keV x-rays  

NASA Astrophysics Data System (ADS)

Phosphor screens which convert x-ray images to visible light images are key components in two-dimensional charge coupled device (CCD) based detector systems used for x-ray diffraction. Some experimental and theoretical aspects of phosphor screen performance are described in this article. The efficiencies of x-ray-to-light conversion were measured using a CCD camera for transmission phosphor screens fabricated from two different phosphor powders, Y2O2S:Eu (P22R) and Gd2O2S:Tb (P43), for screen mass thicknesses of 3-50 mg/cm2 and for x-ray energies of 7-34 keV. A model was developed and evaluated for the dependence of the emitted light brightness on screen thickness and x-ray energy. Inputs to the model are x-ray absorption coefficients available from published compilations, and light attenuation versus thickness data, which were determined experimentally for the phosphors and found to be dominated by scattering rather than absorption. The angular distribution of emitted light, measured for one of the phosphor screens, was found to be nearly Lambertian. Broadening of image features in the x-ray-to-visible-light conversion by phosphors for 19.6 keV x-rays was found to increase approximately linearly with phosphor screen thicknesses in the range of 30-160 ?m, but with a minimum width of 110 ?m for P22R phosphor and 70 ?m for P43 phosphor. In the range of 7-15 keV, maximum brightness was obtained for P43 phosphor screens of about 10 mg/cm2 mass thickness (60 ?m). For P22R screens, the thickness for maximum brightness increased from about 8 mg/cm2 (50 ?m) for 7 keV to more than 46 mg/cm2 (210 ?m) for 15 keV. For 7 keV the maximum brightnesses for P22R and P43 phosphors were about the same. For 10 keV the maximum brightness for P43 phosphor was about 60% greater than the maximum brightness for P22R phosphor samples tested. For 15 keV the maximum brightness for P43 phosphor was again about 60% greater than that for the P22R samples tested. In the range of 20-34 keV, maximum brightness would occur for thicknesses greater than 46 mg/cm2 (210 ?m) for P22R phosphor and greater than 40 mg/cm2 (160 ?m) for P43 phosphor. Comparing the brightness for 90 ?m thickness for the two phosphors, P43 was about 30% brighter for 20 keV, 20% brighter for 24 keV, and 10% brighter for both 29 and 34 keV.

Wang, P.-C.; Cargill, G. S., III

1997-02-01

149

Tables of X-ray mass attenuation coefficients and mass energy-absorption coefficients 1 keV to 20 MeV for elements Z=1 to 92 and 48 additional substances of dosimetric interest  

Microsoft Academic Search

Tables and graphs of the photon mass attenuation coefficient mu\\/rho and the mass energy-absorption coefficient mu(en)\\/rho are presented for all of the elements Z=1 to 92, and for 48 compounds and mixtures of radiological interest. The tables cover energies of the photon (x ray, gamma ray, bremsstrahlung) from 1 keV to 20 MeV. The mu\\/rho values are taken from the

J. H. Hubbell; Stephen M Seltzer

1995-01-01

150

Web 2.0 Applications in China  

NASA Astrophysics Data System (ADS)

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

Zhai, Dongsheng; Liu, Chen

151

29 CFR 20.2 - Definitions.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 true Definitions. 20.2 Section 20.2 Labor Office of the Secretary of Labor FEDERAL...Disclosure of Information to Credit Reporting Agencies § 20.2 Definitions. For purposes of this subpart—...

2010-07-01

152

27 CFR 20.2 - Territorial extent.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Territorial extent. 20.2 Section 20.2 Alcohol, Tobacco Products and Firearms ALCOHOL...DISTRIBUTION AND USE OF DENATURED ALCOHOL AND RUM Scope § 20.2 Territorial extent. (a) This part...

2010-04-01

153

Using Web 2.0 to Collaborate  

ERIC Educational Resources Information Center

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…

Buechler, Scott

2010-01-01

154

Improving the energy response of external beam therapy (EBT) GafChromic{sup TM} dosimetry films at low energies (?100 keV)  

SciTech Connect

Purpose: Purpose of this work is to investigate the effects of varying the active layer composition of external beam therapy (EBT) GafChromic{sup TM} films on the energy dependence of the film, as well as try to develop a new prototype with more uniform energy response at low photon energies (?100?keV). Methods: First, the overall energy response (S{sub AD,} {sub W}(Q)) of different commercial EBT type film models that represent the three different generations produced to date, i.e., EBT, EBT2, and EBT3, was investigated. Pieces of each film model were irradiated to a fixed dose of 2 Gy to water for a wide range of beam qualities and the corresponding S{sub AD,} {sub W}(Q) was measured using a flatbed document scanner. Furthermore, the DOSRZnrc Monte Carlo code was used to determine the absorbed dose to water energy dependence of the film, f(Q). Moreover, the intrinsic energy dependence, k{sub bq}(Q), for each film model was evaluated using the corresponding S{sub AD,} {sub W}(Q) and f(Q). In the second part of this study, the authors investigated the effects of changing the chemical composition of the active layer on S{sub AD,} {sub W}(Q). Finally, based on these results, the film manufacturer fabricated several film prototypes and the authors evaluated their S{sub AD,} {sub W}(Q). Results: The commercial EBT film model shows an under response at all energies below 100 keV reaching 39% ± 4% at about 20 keV. The commercial EBT2 and EBT3 film models show an under response of about 27% ± 4% at 20 keV and an over response of about 16% ± 4% at 40?keV.S{sub AD,} {sub W}(Q) of the three commercial film models at low energies show strong correlation with the corresponding f{sup ?1}(Q) curves. The commercial EBT3 model with 4% Cl in the active layer shows under response of 22% ± 4% at 20 keV and 6% ± 4% at about 40?keV. However, increasing the mass percent of chlorine makes the film more hygroscopic which may affect the stability of the film's readout. The EBT3 film prototype with 7.5% Si shows a significant improvement in the energy response at very low energies compared to the commercial EBT3 films with 4% Cl. It shows under response of 15% ± 5% at about 20 keV to 2% ± 5% at about 40?keV. However, according to the manufacturer, the addition of 7.5% Si as SiO{sub 2} adversely affected the viscosity of the active fluid and therefore affected the potential use in commercial machine coating. The latest commercial EBT3 film model with 7% Al as Al{sub 2}O{sub 3} shows an overall improvement in S{sub AD,} {sub W}(Q) compared to previous commercial EBT3 films. It shows under response at all energies <100 keV, varying from 20% ± 4% at 20 keV to 6% ± 4% at 40?keV. Conclusions: The energy response of films in the energy range <100 keV can be improved by adjusting the active layer chemical composition. Removing bromine eliminated the over response at about 40?keV. The under response at energies ?30 keV is improved by adding 7% Al to the active layer in the latest commercial EBT3 film models.

Bekerat, H., E-mail: hamed.bekerat@mail.mcgill.ca; Devic, S.; DeBlois, F. [Medical Physics Unit, McGill University, Montréal, Québec H3G 1A4, Canada and Department of Radiation Oncology, Jewish General Hospital, Montréal, Québec H3T 1E2 (Canada)] [Medical Physics Unit, McGill University, Montréal, Québec H3G 1A4, Canada and Department of Radiation Oncology, Jewish General Hospital, Montréal, Québec H3T 1E2 (Canada); Singh, K.; Sarfehnia, A.; Seuntjens, J. [Medical Physics Unit, McGill University, Montréal, Québec H3G 1A4 (Canada)] [Medical Physics Unit, McGill University, Montréal, Québec H3G 1A4 (Canada); Shih, Shelley; Yu, Xiang; Lewis, D. [Ashland Specialty Ingredients, 1361 Alps Road, Wayne, New Jersey 07470 (United States)] [Ashland Specialty Ingredients, 1361 Alps Road, Wayne, New Jersey 07470 (United States)

2014-02-15

155

Is 20/20 vision good enough? Visual acuity differences within the normal range predict contour element detection and integration.  

PubMed

Contour integration (CI) combines appropriately aligned and oriented elements into continuous boundaries. Collinear facilitation (CF) occurs when a low-contrast oriented element becomes more visible when flanked by collinear high-contrast elements. Both processes rely at least partly on long-range horizontal connections in early visual cortex, and thus both have been extensively studied to understand visual cortical functioning in aging, development, and clinical disorders. Here, we ask: Can acuity differences within the normal range predict CI or CF? To consider this question, we measured binocular visual acuity and compared subjects with 20/20 vision to those with better-than-20/20 vision (SharpPerceivers) on two tasks. In the CI task, subjects located an integrated shape embedded in varying amounts of noise; in the CF task, subjects detected a low-contrast element flanked by collinear or orthogonal high-contrast elements. In each case, displays were scaled in size to modulate element visibility and spatial frequency (4-12 cycles/deg). SharpPerceivers could integrate contours under noisier conditions than the 20/20 group (p = .0002), especially for high spatial frequency displays. Moreover, although the two groups exhibited similar collinear facilitation, SharpPerceivers could detect the central target with lower contrast at high spatial frequencies (p <. 05). These results suggest that small acuity differences within the normal range-corresponding to about a one line difference on a vision chart-strongly predict element detection and integration. Furthermore, simply ensuring that subjects have normal or corrected-to-normal vision is not sufficient when comparing groups on contour tasks; visual acuity confounds also need to be ruled out. PMID:24845876

Keane, Brian P; Kastner, Sabine; Paterno, Danielle; Silverstein, Steven M

2015-02-01

156

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

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

Dryak, Pavel; Kovar, Petr

2006-01-01

157

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

NASA Astrophysics Data System (ADS)

The objective of this work is to investigate Compton camera technology for spectroscopic imaging of gamma rays in the 100keV to 1MeV range. An efficient, specific purpose Monte Carlo code was developed to investigate the image formation process in Compton cameras. The code is based on a pathway sampling technique with extensive use of variance reduction techniques. The code includes detailed Compton scattering physics, including incoherent scattering functions, Doppler broadening, and multiple scattering. Experiments were performed with two different camera configurations for a scene containing a 75Se source and a 137Cs source. The first camera was based on a fixed silicon detector in the front plane and a CdZnTe detector mounted in the stage. The second camera configuration was based on two CdZnTe detectors. Both systems were able to reconstruct images of 75Se, using the 265keV line, and 137Cs, using the 662keV line. Only the silicon-CdZnTe camera was able to resolve the low intensity 400keV line of 75Se. Neither camera was able to reconstruct the 75Se source location using the 136keV line. The energy resolution of the silicon-CdZnTe camera system was 4% at 662keV. This camera reproduced the location of the 137Cs source by event circle image reconstruction with angular resolutions of 10° for a source on the camera axis and 14° for a source 30° off axis. Typical detector pair efficiencies were measured as 3 x 10-11 at 662keV. The dual CdZnTe camera had an energy resolution of 3.2% at 662keV. This camera reproduced the location of the 137Cs source by event circle image reconstruction with angular resolutions of 8° for a source on the camera axis and 12° for a source 20° off axis. Typical detector pair efficiencies were measured as 7 x 10-11 at 662keV. Of the two prototype camera configurations tested, the silicon-CdZnTe configuration had superior imaging characteristics. This configuration is less sensitive to effects caused by source decay cascades and random coincident events. An implementation of the expectation maximum-maximum likelihood reconstruction technique improved the angular resolution to 6° and reduced the background in all the images. The measured counting rates were a factor of two low for the silicon-CdZnTe camera, and up to a factor of four high for the dual CdZnTe camera compared to simulation. (Abstract shortened by UMI.)

Earnhart, Jonathan Raby Dewitt

158

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

E-print Network

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.

Volker Beckmann; Neil Gehrels; Jack Tueller

2007-04-20

159

The PLATO 2.0 Mission  

E-print Network

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...

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

160

L-shell x-ray-production cross sections in lead by proton bombardment (240--440 keV)  

SciTech Connect

The L-shell x-ray-production process in lead (Pb) by proton impact over the energy range 240--440 keV has been studied. The x rays emitted from a thin (44.4 +- 3.9 ..mu..g/cm/sup 2/) Pb target were detected using a high-purity Ge low-energy photon spectroscopy detector. The total x-ray cross sections and the x-ray cross sections for the Ll, L..cap alpha../sub 1,2/, L..beta..'s, L..gamma../sub 1/, and L..gamma../sub 2,3/ components were determined at 20-keV intervals over the bombarding energy range. The experimental x-ray cross sections were found to be in reasonable agreement with those predicted by perturbed stationary-state (PSS) theory with relativistic (R), energy-loss (E), and Coulomb-deflection (C) corrections (ECPSSR).

Moheb, H.; Bigaouette, R.; Inman, F.W.

1985-12-01

161

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

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

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

2015-04-01

162

Investigation of complete and incomplete fusion in 20Ne + 51V system using recoil range measurement  

NASA Astrophysics Data System (ADS)

Recoil range distributions of evaporation residues, populated in 20Ne + 51V reaction at Elab ? 145 MeV, have been studied to determine the degree of momentum transferred through the complete and incomplete fusion reactions. Evaporation residues (ERs) populated through the complete and incomplete fusion reactions have been identified on the basis of their recoil range in the Al catcher medium. Measured recoil range of evaporation residues have been compared with the theoretical value calculated using the code SRIM. Range integrated cross section of observed ERs have been compared with the value predicted by statistical model code PACE4.

Ali, Sabir; Ahmad, Tauseeef; Kumar, Kamal; Rizvi, I. A.; Agarwal, Avinash; Ghugre, S. S.; Sinha, A. K.; Chaubey, A. K.

2015-01-01

163

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

SciTech Connect

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.

Castleton, Karl J.; Meyer, Philip D.

2009-06-17

164

DISFRAC Version 2.0 Users Guide  

SciTech Connect

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

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

2013-01-01

165

THE ORIGIN OF THE 6.4 keV LINE EMISSION AND H{sub 2} IONIZATION IN THE DIFFUSE MOLECULAR GAS OF THE GALACTIC CENTER REGION  

SciTech Connect

We investigate the origin of the diffuse 6.4 keV line emission recently detected by Suzaku and the source of H{sub 2} ionization in the diffuse molecular gas of the Galactic center (GC) region. We show that Fe atoms and H{sub 2} molecules in the diffuse interstellar medium of the GC are not ionized by the same particles. The Fe atoms are most likely ionized by X-ray photons emitted by Sgr A* during a previous period of flaring activity of the supermassive black hole. The measured longitudinal intensity distribution of the diffuse 6.4 keV line emission is best explained if the past activity of Sgr A* lasted at least several hundred years and released a mean 2-100 keV luminosity {approx}> 10{sup 38} erg s{sup -1}. The H{sub 2} molecules of the diffuse gas cannot be ionized by photons from Sgr A*, because soft photons are strongly absorbed in the interstellar gas around the central black hole. The molecular hydrogen in the GC region is most likely ionized by low-energy cosmic rays, probably protons rather than electrons, whose contribution into the diffuse 6.4 keV line emission is negligible.

Dogiel, V. A.; Chernyshov, D. O. [I. E. Tamm Theoretical Physics Division of P. N. Lebedev Institute of Physics, Leninskii pr. 53, 119991 Moscow (Russian Federation); Tatischeff, V. [Centre de Spectrometrie Nucleaire et de Spectrometrie de Masse, IN2P3/CNRS and Univ Paris-Sud, F-91405 Orsay Campus (France); Cheng, K.-S. [Department of Physics, University of Hong Kong, Pokfulam Road, Hong Kong (Hong Kong); Terrier, R. [Astroparticule et Cosmologie, Universite Paris7/CNRS/CEA, Batiment Condorcet, F-75013 Paris (France)

2013-07-10

166

IEEE SIGNAL PROCESSING LETTERS, VOL. 20, NO. 1, JANUARY 2013 51 Joint Clock Synchronization and Ranging  

E-print Network

IEEE SIGNAL PROCESSING LETTERS, VOL. 20, NO. 1, JANUARY 2013 51 Joint Clock Synchronization and Ranging: Asymmetrical Time-Stamping and Passive Listening Sundeep Prabhakar Chepuri, Student Member, IEEE) is considered in this letter. We propose a novel asymmetrical time-stamping and passive listening (ATPL

Leus, Geert

167

Science Fairs 2.0  

NSDL National Science Digital Library

This resource guide from the Middle School Portal 2 project, written specifically for teachers, provides links to exemplary resources including background information, lessons, career information, and related national science education standards. Looking for some really good ideas from teachers that are currently running very successful science fairs? This wiki page discusses resources that will provide great ideas for you and your students.

Jessica Fries-Gaither

2010-01-01

168

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

NASA Astrophysics Data System (ADS)

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

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

2004-05-01

169

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

SciTech Connect

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

Takeda, Tohoru; Wu Jin; Tsuchiya, Yoshinori; Lwin, Thet-Thet; Itai, Yuji [Institute of Clinical Medicine, University of Tsukuba, Tsukuba-shi, Ibaraki 305-8575 (Japan); Yoneyama, Akio [Advanced Research Laboratory, Hitachi, Ltd., Hatoyama, Saitama, 350-0395 (Japan); Hyodo, Kazuyuki [Material Structure Science, High Energy Accelerator Research Organization, Tsukuba 305-0801 (Japan)

2004-05-12

170

Cusp electron production in 75--300 keV He{sup +} + Ar collisions  

SciTech Connect

Cusp-electron production has been investigated in collisions of 75--300 keV He{sup +} with Ar. The relative contributions from electron capture to the continuum (ECC), transfer ionization (TI), and electron loss to the continuum (ELC) to the total cusp electron production were measured. Over the energy range investigated, ECC was found to decrease from about 86% to 80%, TI decreased from about 12% to 1%, and ELC increased from about 2% to 20%. The present results are consistent with earlier work for He{sup +} and O{sup q+} projectiles.

Plano, V.L. [Michigan State Univ., East Lansing, MI (US); Sarkadi, L.; Zavodszky, P.; Berenyi, D.; Palinkas, J.; Gulyas, L.; Takacs, E.; Toth, L. [Inst. of Nuclear Research, Debrecen (HU); Tanis, J.A. [Western Michigan Univ., Kalamazoo, MI (US)

1992-12-31

171

Student Inquiry and Web 2.0  

ERIC Educational Resources Information Center

Web 2.0 applications are changing how educators interact both with each other and with their students. Educators can use these new Web tools daily to create, share, socialize, and collaborate with students, colleagues, and newly developed network contacts. School librarians are finding that Web 2.0 tools are bringing them more ways to embrace and…

Berger, Pam

2010-01-01

172

DCC Briefing Paper: Web 2.0   

E-print Network

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...

Abbott, Daisy

2010-01-01

173

0% 10% 20% 30% Employment Agency (2)  

E-print Network

1% 3% 25% 8% 28% 15% 20% 0% 10% 20% 30% Other (1) Employment Agency (2) Internet Listing responses to this ques- tion from the 122 "Employed/Full- Time" Syracuse University Career Services Division+ Months After 1 2% Total 74 100% Position Obtained Through # % Employed/Full-Time * 122 76% Employed

Doyle, Robert

174

Trust, Voice, and Library 2.0  

ERIC Educational Resources Information Center

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

Watkins, Candice

2009-01-01

175

Breathing Fire into Web 2.0  

ERIC Educational Resources Information Center

Today's methods of social networking and the technologies that support them offer powerful examples of how educators can connect to the "real" world of client population. To fully engage with the Web 2.0 world, educators work to include aspects of Web 2.0 into their teaching through the use of wikis, forums, and blogs. Administrators are also…

Hardman, Justin; Carpenter, David

2007-01-01

176

20 CFR 219.2 - Definitions.  

Code of Federal Regulations, 2011 CFR

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...

2011-04-01

177

20 CFR 219.2 - Definitions.  

Code of Federal Regulations, 2010 CFR

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...

2010-04-01

178

20 CFR 219.2 - Definitions.  

Code of Federal Regulations, 2012 CFR

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...

2012-04-01

179

20 CFR 219.2 - Definitions.  

Code of Federal Regulations, 2014 CFR

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...

2014-04-01

180

20 CFR 219.2 - Definitions.  

Code of Federal Regulations, 2013 CFR

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...

2013-04-01

181

Schwinger variational approach for a direct excitation of hydrogen-like (Li2+ (1s)) target to the level n=3 by proton impact energies from 9 keV to 3 MeV  

NASA Astrophysics Data System (ADS)

The excitation cross sections for hydrogen-like (Li2+(1s)) to the 3s, 3p and 3d states by proton impact have been calculated in a wide energy range from 9 keV to 3 MeV, using the Schwinger's variational principle within the impact parameter formalism. These cross sections are relevant to controlled nuclear fusion studies [1]. The behaviors of the computed cross sections are in excellent agreement with available theoretical results, obtained by close-coupling method which is those of TCAO of Ermolaev et al [1] and SCE of Hall et al [2].

Khelfaoui, Friha; Lasri, Boumediene; Abbes, Oukacha

2012-06-01

182

Fragmentation of doubly charged HDO, H2O, and D2O molecules induced by proton and monocharged fluorine beam impact at 3 keV  

NASA Astrophysics Data System (ADS)

Doubly charged ions HDO2+, H2O2+, and D2O2+ were prepared selectively to triplet or singlet excited states in collisions with F+ or H+ projectiles at 3 keV. Excitation energies of dications following two-body or three-body dissociation channels were measured and compared with recent calculations using ab initio multi-reference configuration interaction method [Gervais et al., J. Chem. Phys. 131, 024302 (2009)]. For HDO2+, preferential cleavage of O-H rather than O-D bond has been observed and the ratio between the populations of the fragmentation channels OD+_H+ and OH+_D+ were measured. The kinetic energy release has been measured and compared with previous experiments.

Martin, S.; Chen, L.; Brédy, R.; Bernard, J.; Cassimi, A.

2015-03-01

183

Fragmentation of doubly charged HDO, H2O, and D2O molecules induced by proton and monocharged fluorine beam impact at 3 keV.  

PubMed

Doubly charged ions HDO(2+), H2O(2+), and D2O(2+) were prepared selectively to triplet or singlet excited states in collisions with F(+) or H(+) projectiles at 3 keV. Excitation energies of dications following two-body or three-body dissociation channels were measured and compared with recent calculations using ab initio multi-reference configuration interaction method [Gervais et al., J. Chem. Phys. 131, 024302 (2009)]. For HDO(2+), preferential cleavage of O-H rather than O-D bond has been observed and the ratio between the populations of the fragmentation channels OD(+)_H(+) and OH(+)_D(+) were measured. The kinetic energy release has been measured and compared with previous experiments. PMID:25747080

Martin, S; Chen, L; Brédy, R; Bernard, J; Cassimi, A

2015-03-01

184

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

NASA Astrophysics Data System (ADS)

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.

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

2014-03-01

185

Energy-discrimination X-ray computed tomography system utilizing a silicon-PIN detector and its application to 2.0-keV-width K-edge imaging  

NASA Astrophysics Data System (ADS)

Demonstration of narrow-energy-width computed tomography (CT) was carried out by means of energy-discrimination. An X-ray CT system is of a first-generation type and consists of an X-ray generator, a turntable, a translation stage, a two-stage controller, a silicon-PIN detector system with amplifiers, a multi-channel analyzer (MCA), a counter card (CC), and a personal computer (PC). CT is accomplished by repeating the translation and the rotation of an object, and projection curves of the object are obtained by the translation of the moving object. Both photon-energy level and energy width are determined by the MCA, and the pulses of the discriminated event signal from the MCA are counted by CC in conjunction with PC. The maximum count rate was approximately 300 cps (counts per second) with energy widths of 2.0 keV, and energy-discrimination CT was carried out with a photon-energy resolution of 0.15 keV. To perform iodine K-edge CT, X-ray photons with an energy range from 33.2 to 35.2 keV were used. Next, to carry out cerium K-edge CT, an energy range from 40.3 to 42.3 keV was selected.

Hagiwara, Osahiko; Watanabe, Manabu; Sato, Eiichi; Matsukiyo, Hiroshi; Osawa, Akihiro; Enomoto, Toshiyuki; Nagao, Jiro; Sato, Shigehiro; Ogawa, Akira; Onagawa, Jun

2011-05-01

186

Definition of Health 2.0 and Medicine 2.0: A Systematic Review  

PubMed Central

Background During the last decade, the Internet has become increasingly popular and is now an important part of our daily life. When new “Web 2.0” technologies are used in health care, the terms “Health 2.0" or "Medicine 2.0” may be used. Objective The objective was to identify unique definitions of Health 2.0/Medicine 2.0 and recurrent topics within the definitions. Methods A systematic literature review of electronic databases (PubMed, Scopus, CINAHL) and gray literature on the Internet using the search engines Google, Bing, and Yahoo was performed to find unique definitions of Health 2.0/Medicine 2.0. We assessed all literature, extracted unique definitions, and selected recurrent topics by using the constant comparison method. Results We found a total of 1937 articles, 533 in scientific databases and 1404 in the gray literature. We selected 46 unique definitions for further analysis and identified 7 main topics. Conclusions Health 2.0/Medicine 2.0 are still developing areas. Many articles concerning this subject were found, primarily on the Internet. However, there is still no general consensus regarding the definition of Health 2.0/Medicine 2.0. We hope that this study will contribute to building the concept of Health 2.0/Medicine 2.0 and facilitate discussion and further research. PMID:20542857

Engelen, Lucien JLPG; Berben, Sivera AA; Schoonhoven, Lisette

2010-01-01

187

Elastic and inelastic processes in H{sup +}+C{sub 2}H{sub 2} collisions below the 1.5-keV regime  

SciTech Connect

Electron capture and direct elastic scattering in collisions of H{sup +} ions with C{sub 2}H{sub 2} molecules are studied by using a molecular representation within a fully quantum-mechanical approach below 1.5 keV. Calculations are carried out at two different molecular configurations: (i) {ital C}{sub 00{ital v}} symmetry, in which H{sup +} approaches the H atom along a C{emdash}H bond in the acetylene (C{sub 2}H{sub 2}), and (ii) {ital C}{sub 2{ital v}} symmetry, in which H{sup +} approaches perpendicularly toward the midpoint between two carbon atoms. We find that electron capture in the {ital C}{sub 00{ital v}} symmetry configuration takes place preferentially over that in the {ital C}{sub 2{ital v}} symmetry configuration at scattering angles above 15{degree}. The results for the {ital C}{sub 2{ital v}} and {ital C}{sub 00{ital v}} symmetries are comparable in magnitude below 10{degree}, although the {ital C}{sub 2{ital v}} symmetry dominates slightly at still smaller angles. Hence, interferences arising from these molecular configurations in differential cross sections for electron capture and elastic scattering processes are strongly present at angles smaller than a few degrees. Accordingly, the total cross section for the {ital C}{sub 2{ital v}} symmetry is larger by a factor of 3 at 1 keV, and the difference widens as the energy decreases to the eV regime. This is because in {ital C}{sub 2{ital v}} symmetry, H{sup +} can have a larger overlap with the charge distribution of the C{sub 2}H{sub 2} molecule, thus causing a stronger interaction. {copyright} {ital 1996 The American Physical Society.}

Kimura, M. [School of Allied Health Sciences, Yamaguchi University, Ube 755, Yamaguchi (Japan)] [School of Allied Health Sciences, Yamaguchi University, Ube 755, Yamaguchi (Japan); [Institute of Physical and Chemical Research (RIKEN), Wako, Saitama 351-01 (Japan); Li, Y.; Hirsch, G.; Buenker, R.J. [Theoretische Chemie, Bergische Universitaet-Gesamthochschule Wuppertal, D-42097 Wuppertal (Germany)] [Theoretische Chemie, Bergische Universitaet-Gesamthochschule Wuppertal, D-42097 Wuppertal (Germany)

1996-12-01

188

PROPERTIES OF PHANTOM TISSUE-LIKE POLYMETHYLPENTENE IN THE FREQUENCY RANGE 20–70 MHZ  

PubMed Central

Quantitative ultrasound (QUS) has been employed to characterize soft tissues at ordinary abdominal ultrasound frequencies (2–15 MHz) and is beginning application at high frequencies (20–70 MHz). For example, backscatter and attenuation coefficients can be estimated in vivo using a reference phantom. At high frequencies it is crucial that reverberations do not compromise the measurements. Such reverberations can occur between the phantom's scanning window and transducer components as well as within the scanning window between its surfaces. Transducers are designed to minimize reverberations between the transducer and soft tissue. Thus, the acoustic impedance of a phantom scanning window should be tissue-like; polymethylpentene (TPX) is commonly used because of its tissue-like acoustic impedance. For QUS it is also crucial to correct for the transmission coefficient of the scanning window. Computation of the latter requires knowledge of the ultrasonic properties, viz, density, speed and attenuation coefficients. This work reports values for the ultrasonic properties of two versions of TPX over the high frequency range. One form (TPX film) is used as a scanning window on high frequency phantoms, and at 40 MHz and 22°C was found to have an attenuation coefficient of 120 dB/cm and a propagation speed of 2093 m/s. PMID:21723451

Madsen, Ernest L; Deaner, Meagan E; Mehi, James

2011-01-01

189

Carbon Capture (Carbon Cycle 2.0)  

SciTech Connect

Berend Smit 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/

Smit, Berend

2010-02-03

190

Carbon Capture (Carbon Cycle 2.0)  

ScienceCinema

Berend Smit 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/

Smit, Berend

2011-06-08

191

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

Microsoft Academic Search

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

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

1996-01-01

192

Technical Note: Influence of the phantom material on the absorbed-dose energy dependence of the EBT3 radiochromic film for photons in the energy range 3 keV–18 MeV  

SciTech Connect

Purpose: Water is the reference medium for radiation therapy dosimetry, but for film dosimetry it is more practical to use a solid phantom. As the composition of solid phantoms differs from that of water, the energy dependence of film exposed within solid phantoms may also differ. The energy dependence of a radiochromic film for a given beam quality Q (energy for monoenergetic beams) has two components: the intrinsic energy dependence and the absorbed-dose energy dependence f(Q), the latter of which can be calculated through a Monte Carlo simulation of radiation transport. The authors used Monte Carlo simulations to study the influence of the phantom material on the f(Q) of the EBT3 radiochromic film (Ashland Specialty Ingredients, Wayne, NJ) for photon beams with energies between 3 keV and 18 MeV. Methods: All simulations were carried out with the general-purpose Monte Carlo code PENELOPE 2011. The geometrical model consisted of a cylindrical phantom, with the film positioned at different depths depending on the initial photon energy. The authors simulated monoenergetic parallel photon beams and x-ray beams from a superficial therapy system. To validate their choice of simulation parameters, they also calculated f(Q) for older film models, EBT and EBT2, comparing with published results. In addition to water, they calculated f(Q) of the EBT3 film for solid phantom materials commonly used for film dosimetry: RW1 and RW3 (PTW-Freiburg, Freiburg, Germany), Solid Water (Gammex-RMI, Madison, WI), and PMMA. Finally, they combined their calculated f(Q) with published overall energy response data to obtain the intrinsic energy dependence of the EBT3 film in water. Results: The calculated f(Q) for EBT and EBT2 films was statistically compatible with previously published data. Between 10 keV and 18 MeV, the variation found in f(Q) of the EBT3 film for water was within 2.3%, with a standard statistical uncertainty less than 1%. If the quantity dose-to-water in the phantom is considered, which is the common practice in radiation dosimetry, the maximum difference of energy dependence for the solid phantoms with respect to water is about 6%, at an energy of 50 keV. Conclusions: The EBT3 film shows a reasonably constant absorbed-dose energy dependence when irradiated in water. If the dose-to-water in the phantom is considered, the maximum difference of EBT3 film energy dependence with the solid phantoms studied with respect to water is about 6% (at an energy of 50 keV). The reported overall energy dependence of the EBT3 film in water at energies below 100 keV is mainly due to the intrinsic energy dependence.

Hermida-López, M., E-mail: mhermida@vhebron.net [NCTeam, Strahlenklinik, Universitätsklinikum Essen, Hufelandstraße 55, Essen D-45122, Germany and Servei de Física i Protecció Radiològica, Hospital Universitari Vall d’Hebron, Pg. Vall d’Hebron 119-129, Barcelona 08035 (Spain); Lüdemann, L.; Flühs, A. [Medical Physics, Strahlenklinik, Universitätsklinikum Essen, Hufelandstraße 55, Essen D-45122 (Germany); Brualla, L. [NCTeam, Strahlenklinik, Universitätsklinikum Essen, Hufelandstraße 55, Essen D-45122 (Germany)

2014-11-01

193

The PLATO 2.0 Mission  

NASA Astrophysics Data System (ADS)

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.

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

194

Web 2.0 and You!  

NSDL National Science Digital Library

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.

Brenda A. Dyck

195

Business 2.0 Web Guide  

NSDL National Science Digital Library

According to one of its own brochures, "Business 2.0 is the essential tool for navigating today's relentlessly changing marketplace, particularly as it's driven by the Internet and other technologies." In both print and electronic versions, Business 2.0 does cover an incredible amount of ground, including day-to-day and month-to-month information and offering extensive subject lists of its material, broken down by general subjects -- from management and marketing to Enron and the Internet. Not only clearly in touch with today's business world, Business 2.0 promises to put its readers in touch with it through company links, as well as through straightforward contact lists. While Business 2.0 is open for anyone's consultation, registered readers are granted greater access privileges to archived and premium content.

196

M-shell x-ray production cross sections for 19 elements in the range Z=54-92 by H/sup +/, He/sup +/ and He/sup + +/ ions from 300 keV to 40 MeV. [Xe, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Yb, Hf, Ta, W, Pt, Au, Hg, Pb, Bi, and U  

SciTech Connect

In this report, the measurements done over the last three decades at various laboratories are surveyed. The elements studied were Xe, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Yb, Hf, Ta, W, Pt, Au, Hg, Pb, Bi, and U. The projectile energies investigated range from 300 keV to 40 MeV for the protons and 250 keV to 2.5 MeV for He/sup +/ ions. Also reported are the M-shell x-ray production cross sections of some rare-earth elements recently measured at NTSU. For these measurements the energy of incident /sup 1/H/sup +/ and /sup 4/He/sup +/ ions ranged from 0.25 to 2.5 MeV. The experimental data are compared to the M-shell ionization cross section predictions of first Born approximation, i.e. the PWBA for direct ionization plus the OBK of Nikolaev for electron capture. Comparison is also made with the theory by Brandt and Lapicki that goes beyond the first Born approximation, i.e. the ECPSSR approach which accounts for the Energy loss, Coulomb deflection and Relativistic effects in the Perturbed Stationary State theory.

Mehta, R.; Duggan, J.L.; Kocur, P.M.; Lapicki, G.; McDaniel, F.D.; Price, J.L.

1983-04-01

197

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

NASA Astrophysics Data System (ADS)

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.

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

2010-07-01

198

Lost in Web 2.0 Cyberspace?  

ERIC Educational Resources Information Center

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

Fallon, Julia

2008-01-01

199

The PLATO 2.0 mission  

NASA Astrophysics Data System (ADS)

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.

Rauer, H.

2013-09-01

200

Web Lectures and Web 2.0  

Microsoft Academic Search

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

Markus Ketterl; Robert Mertens; Oliver Vornberger

2008-01-01

201

Combustion and Carbon Cycle 2.0 and Computation in CC 2.0 (Carbon Cycle 2.0)  

SciTech Connect

Robert Cheng and Juan Meza provide two presentations in one session 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/

Cheng, Robert K; Meza, Juan

2010-02-03

202

Combustion and Carbon Cycle 2.0 and Computation in CC 2.0 (Carbon Cycle 2.0)  

ScienceCinema

Robert Cheng and Juan Meza provide two presentations in one session 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/

Cheng, Robert K; Meza, Juan

2011-06-08

203

43 CFR 4120.3-2 - Cooperative range improvement agreements.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 false Cooperative range improvement agreements. 4120.3-2...MANAGEMENT, DEPARTMENT OF THE INTERIOR RANGE MANAGEMENT (4000) GRAZING ADMINISTRATION-EXCLUSIVE...Management § 4120.3-2 Cooperative range improvement agreements. (a) The...

2013-10-01

204

43 CFR 4120.3-2 - Cooperative range improvement agreements.  

Code of Federal Regulations, 2011 CFR

... 2011-10-01 false Cooperative range improvement agreements. 4120.3-2...MANAGEMENT, DEPARTMENT OF THE INTERIOR RANGE MANAGEMENT (4000) GRAZING ADMINISTRATION-EXCLUSIVE...Management § 4120.3-2 Cooperative range improvement agreements. (a) The...

2011-10-01

205

43 CFR 4120.3-2 - Cooperative range improvement agreements.  

Code of Federal Regulations, 2012 CFR

... 2012-10-01 false Cooperative range improvement agreements. 4120.3-2...MANAGEMENT, DEPARTMENT OF THE INTERIOR RANGE MANAGEMENT (4000) GRAZING ADMINISTRATION-EXCLUSIVE...Management § 4120.3-2 Cooperative range improvement agreements. (a) The...

2012-10-01

206

43 CFR 4120.3-2 - Cooperative range improvement agreements.  

Code of Federal Regulations, 2014 CFR

... 2014-10-01 false Cooperative range improvement agreements. 4120.3-2...MANAGEMENT, DEPARTMENT OF THE INTERIOR RANGE MANAGEMENT (4000) GRAZING ADMINISTRATION-EXCLUSIVE...Management § 4120.3-2 Cooperative range improvement agreements. (a) The...

2014-10-01

207

Global Impacts (Carbon Cycle 2.0)  

SciTech Connect

Ashok Gadgil, Faculty Senior Scientist and Acting Director, EETD, also Professor of Environmental Engineering, UC Berkeley, 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/

Gadgil, Ashok [EETD and UC Berkeley] [EETD and UC Berkeley

2010-02-02

208

Global Impacts (Carbon Cycle 2.0)  

ScienceCinema

Ashok Gadgil, Faculty Senior Scientist and Acting Director, EETD, also Professor of Environmental Engineering, UC Berkeley, 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/

Gadgil, Ashok [EETD and UC Berkeley

2011-06-08

209

The Isotope Effect to the IR Emissions of CO and CO2 produced by 15 keV H3+ irradiation of H2O (D2O)\\/ CO, CO2, CH4 or CH3OH icy mixtures  

Microsoft Academic Search

Simulation of ices covered astronomical surfaces irradiated by 15 keV H3+. We have measured the particle irradiation of interstellar icy materials such as H2O mixed with CH4, CO, CO2, and CH3OH resulting the synthesis of CO and CO2. The technique used to identify and quantify the synthesized species has been infrared spectroscopy. Irradiation of pure water ice produces OH and

C. Lee; W. Ip; C. Lin; C. Chou

2008-01-01

210

Using Web 2.0 for Learning in the Community  

ERIC Educational Resources Information Center

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,…

Mason, Robin; Rennie, Frank

2007-01-01

211

Web 2.0 and Pharmacy Education  

PubMed Central

New types of social Internet applications (often referred to as Web 2.0) are becoming increasingly popular within higher education environments. Although developed primarily for entertainment and social communication within the general population, applications such as blogs, social video sites, and virtual worlds are being adopted by higher education institutions. These newer applications differ from standard Web sites in that they involve the users in creating and distributing information, hence effectively changing how the Web is used for knowledge generation and dispersion. Although Web 2.0 applications offer exciting new ways to teach, they should not be the core of instructional planning, but rather selected only after learning objectives and instructional strategies have been identified. This paper provides an overview of prominent Web 2.0 applications, explains how they are being used within education environments, and elaborates on some of the potential opportunities and challenges that these applications present. PMID:19960079

Fox, Brent I.

2009-01-01

212

ePrompter 2.0  

NSDL National Science Digital Library

Oh, the bother of checking multiple email accounts! For those who are bothered by such matters, never fear, as ePrompter 2.0 is here. ePrompter 2.0 lets users automatically check up to sixteen different password-protected email accounts, including such popular services as those offered by AIM, Hotmail, Gmail, and so on. Visitors can even make use of five screensavers that allow them to see how many new messages they have in each account. This version of ePrompter is compatible with computers running any version of Windows.

2007-01-01

213

RAS Pathway v2.0  

Cancer.gov

Posted: January 13, 2015 RAS Pathway v2.0 January 13, 2015 by Frank McCormick Enlarge The diagram shows 227 genes arranged in 65 groups containing one to 29 genes per group.  The proteins represented by gene names in a group are thought to carry

214

COMPONENTVersion 2.0 Tree Comparsion Software  

E-print Network

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

Page, Roderic

215

Change Management Meets Web 2.0  

ERIC Educational Resources Information Center

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

Gale, Doug

2008-01-01

216

Looking for Collection 2.0  

ERIC Educational Resources Information Center

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,…

Buczynski, James A.

2008-01-01

217

Professional Development and Web 2.0  

ERIC Educational Resources Information Center

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…

Jakes, David

2007-01-01

218

Version 2.0 User's Guide  

E-print Network

Constructors 47 TestBenches 49 CHAPTER 4 Processes 53 Basics 54 Method Process 54 Thread Processes 56 Clocked Thread Process 59 Wait Until 63 Watching 64 Local Watching 67 CHAPTER 5 Ports and Signals 71 Reading 77 Signal Binding 78 #12;SystemC 2.0 User's Guide v Clocks 80 CHAPTER 6 Data Types 83 Type sc_bit 84

Silvano, Cristina

219

Disseminating information via Web 2.0  

Microsoft Academic Search

It is wonderful to connect with you and have the opportunity to interact on our shared interests in all aspects of our profession. As a brief introduction, my research interests are currently in network efficiency and security, as well as bioinformatics (biodiversity informatics), Internet programming (the use of Web 2.0 technologies to disseminate information) and certainly pedagogy in the CS

Nazli Hardy

2008-01-01

220

RADIO CONTROL CRICKET V2.0  

E-print Network

_OUT ADC0 (RSSI) RADIO CONTROL CRICKET V2.0 NETWORKS AND MOBILE SYSTEMS GROUP CSAIL@MIT LEAD DESIGNER: NISSANKA B. PRIYANTHA 6310-0335-01 A MTS450CA CRICKET RS232 Crossbow Technology 41 Daggett Drive San Jose

221

Do Web 2.0 Right  

ERIC Educational Resources Information Center

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…

Light, Daniel

2011-01-01

222

Web 2.0 and Geospatial Convergence  

E-print Network

© 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...

Zeiss, Geoff

2007-11-14

223

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...

224

Charge transfer in collisions of B{sup 2+}({sup 2}{ital S},{sup 2}{ital P}) and B{sup 3+}({sup 1}{ital S}) ions with He atoms below 200 keV  

SciTech Connect

Charge transfer in B{sup 2+}({sup 2}{ital S},{sup 2}{ital P})+He and in B{sup 3+}({sup 1}{ital S})+He collisions is studied theoretically by using a semiclassical molecular representation with 8 and 12 molecular channels for B{sup 2+} and B{sup 3+} on He systems, respectively, at collision energies between 200 eV and 200 keV for the former and between 600 eV and 50 keV for the latter. The {ital ab} {ital initio} potential curves and nonadiabatic coupling matrix elements are obtained from the multireference single- and double-excitation configuration-interaction (MRD-CI) calculations for the B{sup 2+}-He system and a pseudopotential-modified configuration-interaction method for the B{sup 3+}-He system. The present cross sections for charge transfer by the ground state B{sup 2+} ions are found to have a broad maximum with a magnitude as large as 2{times}10{sup {minus}15} cm{sup 2} at 100 keV and those by an excited B{sup 2+}({sup 2}{ital P}) state are found to be larger by a factor of 6 than those by the ground state in the same energy regime. B{sup 2+}-excitation cross sections are smaller than those for charge transfer below 1 keV, while they increasingly dominate above this energy. The present total charge-transfer cross section for B{sup 3+} in collisions with He is similar to that obtained in earlier work by Gargaud {ital et} {ital al}. [J. Phys. B {bold 27}, 3985 (1994)] both in magnitude and energy dependence, but is found to show slightly different B{sup 2+}(2{ital s}) and B{sup 2+}(2{ital p}) production ratio. {copyright} {ital 1996 The American Physical Society.}

Kimura, M. [School of Allied Health Sciences, Yamaguchi University, 755 Ube, Yamaguchi (Japan)] [School of Allied Health Sciences, Yamaguchi University, 755 Ube, Yamaguchi (Japan); [The Institute of Physical and Chemical Research (RIKEN), Wako, Saitama 351-01 (Japan); Suzuki, S.; Shimakura, N. [Department of Chemistry, Niigata University, Niigata (Japan)] [Department of Chemistry, Niigata University, Niigata (Japan); Gu, J.P.; Hirsch, G.; Buenker, R.J. [Theoretische Chemie, Bergische Universitaet-Gesamthochschule Wuppertal, D-42097 Wuppertal (Germany)] [Theoretische Chemie, Bergische Universitaet-Gesamthochschule Wuppertal, D-42097 Wuppertal (Germany); Shimamura, I. [The Institute of Physical and Chemical Research (RIKEN), Wako, Saitama 351-01 (Japan)] [The Institute of Physical and Chemical Research (RIKEN), Wako, Saitama 351-01 (Japan)

1996-10-01

225

Lunar Laser Ranging Experiment for Japanese SELENE-2 landing mission  

NASA Astrophysics Data System (ADS)

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.

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

226

Short- and medium-range order in Zr[subscript 80]Pt[subscript 20] liquids  

SciTech Connect

The atomic structures in equilibrium and supercooled liquids of Zr{sub 80}Pt{sub 20} were determined as a function of temperature by in situ high-energy synchrotron diffraction studies of the levitated liquids (containerless processing) using the beamline electrostatic levitation (BESL) technique. The presence of a pronounced pre-peak at q - 1.7 {angstrom}{sup -1} in the static structure factor indicates medium-range order (MRO) in the liquid. The position and intensity of the pre-peak remain constant with cooling, indicating that the MRO is already present in the liquid above its melting temperature. An analysis of the liquid atomic structures obtained using the Reverse Monte Carlo method utilizing both the structure factor S(q) from x-ray diffraction experiments and the partial pair-correlation functions from ab initio molecular dynamics simulations show that the pre-peak arises from a Pt-Pt correlation that can be identified with icosahedral short-range order around the Pt atoms. The local atomic ordering is dominated by icosahedral-like structures, raising the nucleation barrier between the liquid and these phases, thus assisting glass formation.

Mauro, N.A.; Wessels, V.; Bendert, J.C.; Klein, S.; Gangopadhyay, A.K.; Kramer, M.J.; Hao, S.G.; Rustan, G.E.; Kreyssig, A.; Goldman, A.I.; Kelton, K.F. (WU); (ETH Zurich); (Iowa State); (IMW-Germany)

2011-12-09

227

Guaranteeing Correctness and Availability in P2P Range Indices  

E-print Network

Guaranteeing Correctness and Availability in P2P Range Indices Prakash Linga, Adina Crainiceanu}@cs.cornell.edu ABSTRACT New and emerging P2P applications require sophisticated range query capability and also have been recent work on developing new P2P range indices, none of these indices guarantee correctness

228

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.

229

STRANAL-PMC Version 2.0  

NASA Technical Reports Server (NTRS)

Version 2.0 of the Strain Rate Dependent Analysis of Polymer Matrix Composites (STRANAL-PMC) software has been released. A prior version was reported in Analyzing Loads and Strains in Polymer- Matrix Composites (LEW-17227), NASA Tech Briefs, Vol. 26, No. 11 (November 2002), page 36. To recapitulate: Modified versions of constitutive equations of viscoplasticity of metals are used to represent deformation of a polymeric matrix. The equations are applied in a micromechanical approach, proceeding upward from slices of unit cells, through the ply level, to the laminate level. The constitutive equations are integrated in time by a Runge- Kutta technique. To predict the ultimate strength of each composite ply, failure criteria are implemented within the micromechanics. The inputs to STRANAL-PMC are the laminate geometry, properties of the fiber and matrix materials, and applied stress or strain versus time. The outputs are time-dependent stresses and strains at the slice, ply, and laminate levels. The improvements in version 2.0 include more rigorous representation of hydrostatic- stress effects in the matrix, refinement and extension of ply failure models, and capabilities to analyze transverse shear stresses. Version 2.0 can be implemented as a material-model code within transient dynamic finite-element codes.

Goldberg, Robert; Carney, Kelly S.; Binienda, Wieslaw; Chattopadhyay, Aditi

2006-01-01

230

Solar Fuels and Carbon Cycle 2.0 (Carbon Cycle 2.0)  

ScienceCinema

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/

Alivisatos, Paul

2011-06-03

231

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

SciTech Connect

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/

Bill Collins

2010-02-09

232

Solar Fuels and Carbon Cycle 2.0 (Carbon Cycle 2.0)  

SciTech Connect

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/

Alivisatos, Paul

2010-02-04

233

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

ScienceCinema

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/

Bill Collins

2010-09-01

234

1 CFR 20.2 - Preparation of agency statements.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Preparation of agency statements. 20.2 Section 20.2 General Provisions ADMINISTRATIVE COMMITTEE OF THE...OF THE UNITED STATES GOVERNMENT MANUAL STATEMENTS § 20.2 Preparation of agency statements. In...

2010-01-01

235

50 CFR 20.2 - Relation to other provisions.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Relation to other provisions. 20.2 Section 20.2 Wildlife and Fisheries UNITED STATES FISH AND...CONTINUED) MIGRATORY BIRD HUNTING Introduction § 20.2 Relation to other provisions. (a) Migratory...

2010-10-01

236

An accuracy assessment of photo-ionization cross-section datasets for 1-2 keV x-rays in light elements using PIXE  

NASA Astrophysics Data System (ADS)

Proton-induced x-ray emission (PIXE) was used to assess the accuracy of the National Institute of Standards and Technology XCOM and FFAST photo-ionization cross-section databases in the low energy region (1-2 keV) for light elements. Characteristic x-ray yields generated in thick samples of Mg, Al and Si in elemental and oxide form, were compared to fundamental parameters computations of the expected x-ray yields; the database for this computation included XCOM attenuation coefficients. The resultant PIXE instrumental efficiency constant was found to differ by 4-6% between each element and its oxide. This discrepancy was traced to use of the XCOM Hartree-Slater photo-electric cross-sections. Substitution of the FFAST Hartree-Slater cross-sections reduced the effect. This suggests that for 1-2 keV x-rays in light element absorbers, the FFAST predictions of the photo-electric cross-sections are more accurate than the XCOM values.

Heirwegh, C. M.; Pradler, I.; Campbell, J. L.

2013-09-01

237

Launch vehicle effluent measurements during the August 20, 1977, Titan 3 launch at Air Force Eastern Test Range  

NASA Technical Reports Server (NTRS)

Airborne effluent measurements within the launch cloud and visible and infrared measurements of cloud physical behavior are discussed. Airborne effluent measurements include concentrations of HCl, Cl2, NO, NOX, and particulates as a function of time during each sampling pass through the exhaust cloud. The particle size distribution was measured for each pass through the cloud. Mass concentration as a function of particle diameter was measured over the size range of 0.05- to 25 micron diameter, and particle number density was measured as a function of diameter over a size range of 0.5 to 7.5 micron. Effluent concentrations in the cloud ranged from about 30 ppm several minutes after launch to about 1 to 2 ppm at 100 minutes. Maximum Cl2 concentrations were about 40 to 55 ppb and by 20 minutes were less than 1.0 ppb. A tabulated listing of the airborne data is given in the appendix. Usable cloud imaging data were limited to the first 16 minutes after launch.

Woods, D. C.; Bendura, R. J.; Wornom, D. E.

1979-01-01

238

33 CFR 334.20 - Gulf of Maine off Cape Small, Maine; naval aircraft practice mining range area.  

Code of Federal Regulations, 2010 CFR

... 2010-07-01 2010-07-01 false Gulf of Maine off Cape Small, Maine; naval aircraft practice mining range area. 334...RESTRICTED AREA REGULATIONS § 334.20 Gulf of Maine off Cape Small, Maine; naval aircraft practice...

2010-07-01

239

Herwig++ 2.0 beta release note.  

E-print Network

ar X iv :h ep -p h/ 06 02 06 9v 1 8 F eb 2 00 6 Cavendish-HEP-06/05 CERN-PH-TH/2006-021 IFJPAN-IV-2006-2 IPPP/06/09 KA-TP-02-2006 February 2006 Herwig++ 2.0? Release Note S. Gieseke Institute fu¨r Theoretische Physik, Karlsruhe E-mail: gieseke... of the gauge bosons with respect to the FORTRAN HERWIG 6.5 without matrix element corrections. The pT distributions of Z and W bosons, at the Tevatron and LHC, are compared to HERWIG6.5 in Figs 1 and 2 respectively. 3 Other Changes • A number of changes...

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

240

Correlation between multiple ionization and fragmentation of C2H6 in charge-changing collisions with 580 -keV C+  

NASA Astrophysics Data System (ADS)

We investigate correlations between multiple ionization and fragmentation processes of the ethane molecule in collisions with 580 -keV C+ ions under single-electron capture and loss conditions. Employing an electron counting technique, we directly obtain number distributions of ionized electrons, which correspond to distributions of multiple ionization probabilities of ethane. In addition, fragmentation patterns as a function of the charge state r of intermediate parent ions C2H6 r +* are obtained from coincidence measurements between the time of flight of the product ions and the number of electrons emitted. Fragmentation patterns in the different charge-changing conditions reveal a crucial role of the internal excitation in the fragmentation processes. Also, we provide clear evidence of strong selectivity on the parent charge state for formation of the H3 + ion, which is exclusively generated through doubly charged parent ions C2H6 2 +* .

Majima, T.; Murai, T.; Kishimoto, T.; Adachi, Y.; Yoshida, S. O.; Tsuchida, H.; Itoh, A.

2014-12-01

241

UQTk version 2.0 user manual.  

SciTech Connect

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.

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

2013-10-01

242

41 CFR 60-20.2 - Recruitment and advertisement.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Recruitment and advertisement. 60-20.2 Section 60-20...GUIDELINES § 60-20.2 Recruitment and advertisement. (a) Employers engaged in recruiting...occupation qualification. (b) Advertisement in newspapers and other media...

2013-07-01

243

41 CFR 60-20.2 - Recruitment and advertisement.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 false Recruitment and advertisement. 60-20.2 Section 60-20...GUIDELINES § 60-20.2 Recruitment and advertisement. (a) Employers engaged in recruiting...occupation qualification. (b) Advertisement in newspapers and other media...

2014-07-01

244

41 CFR 60-20.2 - Recruitment and advertisement.  

Code of Federal Regulations, 2012 CFR

...2009-07-01 true Recruitment and advertisement. 60-20.2 Section 60-20...GUIDELINES § 60-20.2 Recruitment and advertisement. (a) Employers engaged in recruiting...occupation qualification. (b) Advertisement in newspapers and other media...

2012-07-01

245

41 CFR 60-20.2 - Recruitment and advertisement.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 true Recruitment and advertisement. 60-20.2 Section 60-20...GUIDELINES § 60-20.2 Recruitment and advertisement. (a) Employers engaged in recruiting...occupation qualification. (b) Advertisement in newspapers and other media...

2010-07-01

246

41 CFR 60-20.2 - Recruitment and advertisement.  

Code of Federal Regulations, 2011 CFR

...2009-07-01 true Recruitment and advertisement. 60-20.2 Section 60-20...GUIDELINES § 60-20.2 Recruitment and advertisement. (a) Employers engaged in recruiting...occupation qualification. (b) Advertisement in newspapers and other media...

2011-07-01

247

36 CFR 222.2 - Management of the range environment.  

Code of Federal Regulations, 2012 CFR

...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...

2012-07-01

248

36 CFR 222.2 - Management of the range environment.  

Code of Federal Regulations, 2014 CFR

...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...

2014-07-01

249

36 CFR 222.2 - Management of the range environment.  

Code of Federal Regulations, 2013 CFR

...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...

2013-07-01

250

36 CFR 222.2 - Management of the range environment.  

Code of Federal Regulations, 2011 CFR

...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...

2011-07-01

251

Bringing Web 2.0 to bioinformatics  

PubMed Central

Enabling deft data integration from numerous, voluminous and heterogeneous data sources is a major bioinformatic challenge. Several approaches have been proposed to address this challenge, including data warehousing and federated databasing. Yet despite the rise of these approaches, integration of data from multiple sources remains problematic and toilsome. These two approaches follow a user-to-computer communication model for data exchange, and do not facilitate a broader concept of data sharing or collaboration among users. In this report, we discuss the potential of Web 2.0 technologies to transcend this model and enhance bioinformatics research. We propose a Web 2.0-based Scientific Social Community (SSC) model for the implementation of these technologies. By establishing a social, collective and collaborative platform for data creation, sharing and integration, we promote a web services-based pipeline featuring web services for computer-to-computer data exchange as users add value. This pipeline aims to simplify data integration and creation, to realize automatic analysis, and to facilitate reuse and sharing of data. SSC can foster collaboration and harness collective intelligence to create and discover new knowledge. In addition to its research potential, we also describe its potential role as an e-learning platform in education. We discuss lessons from information technology, predict the next generation of Web (Web 3.0), and describe its potential impact on the future of bioinformatics studies. PMID:18842678

Zhang, Zhang; Cheung, Kei-Hoi

2009-01-01

252

Latitude variation of recurrent MeV-energy proton flux enhancements in the heliocentric radial range 11 t 20 AU and possible correlation with solar coronal hole dynamics  

Microsoft Academic Search

Recurrent low energy (> or approx. =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°S to 23°N and the heliocentric radial range 11 to 20 AU. After a period of rather high correlation between fluxes

S. P. Christon; E. C. Stone

1985-01-01

253

Anwendungen und Technologien des Web 2.0: Ein berblick  

E-print Network

betreffende Modeworte wie Enterprise 2.0, Business 2.0, Marketing 2.0, Identity 2.0 oder Web 3.0 [15] ­ dieAnwendungen und Technologien des Web 2.0: Ein �berblick Alexander Stocker1 und Klaus Tochtermann1 2 for Networked Media, Joanneum Research3 Zusammenfassung: Das World Wide Web (im folgenden kurz als Web be

Hammerton, James

254

Web 2.0 and Critical Information Literacy  

ERIC Educational Resources Information Center

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…

Dunaway, Michelle

2011-01-01

255

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

ScienceCinema

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/

Alivisatos, Paul

2011-06-08

256

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

SciTech Connect

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/

Collins, Bill

2010-02-01

257

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

SciTech Connect

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/

Alivisatos, Paul

2010-02-01

258

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

ScienceCinema

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/

Collins, Bill

2011-06-08

259

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

E-print Network

to a quantum entanglement effect between the scattered neu- tron and the two protons of the H2O molecule. When one of the protons of a H2O molecule is replaced by a deuteron (by adding D2O to light water. This induces a reduction of the cross section per proton below the cross section for a single isolated proton

Danon, Yaron

260

The Solar Wind Charge-Transfer X-Ray Emission in the 1\\/4 keV Energy Range: Inferences on Local Bubble Hot Gas at Low Z  

Microsoft Academic Search

We present calculations of the heliospheric solar wind charge-exchange (SWCX) emission spectra and the resulting contributions of this diffuse background in the ROSAT 1\\/4 keV bands. We compare our results with the soft X-ray background (SXRB) emission detected in front of 378 identified shadowing regions during the ROSAT All-Sky Survey. This foreground component is principally attributed to the hot gas

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

2009-01-01

261

FLEXAN (version 2.0) user's guide  

NASA Technical Reports Server (NTRS)

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

Stallcup, Scott S.

1989-01-01

262

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

NASA Astrophysics Data System (ADS)

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.

Luo, Tianyong

2011-01-01

263

Gordon and Mike's ICT Podcast: Web 2.0 Spawns Office 2.0  

NSDL National Science Digital Library

Gordon and Mike's ICT Podcast offers perspectives on the information and communication technologies (ICT) industries from Gordon Snyder and Mike Qaissaunee. In this podcast, Mike and Gordon discuss how the growing services offered via webware are eliminating the need for locally-installed software, ushering in the era of Office 2.0 with Web 2.0. The running time for the show is 33:08. This podcast is available for direct download in mp3 format from the Libsyn site, or click here to subscribe to the whole series in iTunes.

Qaissaunee, Michael

264

18 CFR 20.2 - Regulation of issuance of securities.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Regulation of issuance of securities. 20.2 Section 20.2 Conservation of Power and Water Resources FEDERAL...SUBJECT TO SECTIONS 19 AND 20 OF THE FEDERAL POWER ACT § 20.2 Regulation of issuance of securities. The...

2010-04-01

265

BSD Portals for LINUX 2.0  

NASA Technical Reports Server (NTRS)

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

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

1999-01-01

266

Variable Gap Undulator for 1.5-48 Kev Free Electron Laser at Linac Coherent Light Source  

SciTech Connect

We study the feasibility of generating femtosecond duration Free-Electron Laser with a variable photon energy from 1.5 to 48 keV, using an electron bunch with the same characteristics of the LINAC Coherent Light Source (LCLS) bunch, and a planar undulator with additional focusing. We assume that the electron bunch energy can be changed, and the undulator has a variable gap, allowing a variable undulator parameter. It is assumed to be operated in an ultra-low charge and ultra-short pulse regime. We study the feasibility of a tunable, short pulse, X-ray FEL with photon energy from 1.5 to 48 keV, using an electron beam like the one in the LCLS and a 2:5 cm period, variable gap, planar undulator. The beam energy changes from 4.6 to 13.8 GeV, the electorn charge is kept at 10 pC, and the undulator parameter varies from 1 to 3. The undulator length needed to saturate the 48 keV FEL is about 55 m, with a peak power around 5 GW. At longer wavelength the saturation length is as short as 15 m, and the peak power around 20 GW. The results from the analytical models and the GENESIS simulations show that the system is feasible. The large wavelength range, full tunability and short, few femtosecond pulses, together with the large peak power, would provide a powerful research tool.

Pellegrini, C.; /UCLA; Wu, J.; /SLAC; ,

2011-08-17

267

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

ERIC Educational Resources Information Center

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…

Arya, Harsh Bardhan; Mishra, J. K.

2012-01-01

268

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...

269

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

Microsoft Academic Search

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 libraries provide access to their collections and user support for that access.

Harsh Bardhan Arya; J. K. Mishra

2012-01-01

270

Enabling Problem Based Learning through Web 2.0 Technologies: PBL 2.0  

ERIC Educational Resources Information Center

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…

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

2012-01-01

271

The r-Java 2.0 code: nuclear physics  

NASA Astrophysics Data System (ADS)

Aims: We present r-Java 2.0, a nucleosynthesis code for open use that performs r-process calculations, along with a suite of other analysis tools. Methods: Equipped with a straightforward graphical user interface, r-Java 2.0 is capable of simulating nuclear statistical equilibrium (NSE), calculating r-process abundances for a wide range of input parameters and astrophysical environments, computing the mass fragmentation from neutron-induced fission and studying individual nucleosynthesis processes. Results: In this paper we discuss enhancements to this version of r-Java, especially the ability to solve the full reaction network. The sophisticated fission methodology incorporated in r-Java 2.0 that includes three fission channels (beta-delayed, neutron-induced, and spontaneous fission), along with computation of the mass fragmentation, is compared to the upper limit on mass fission approximation. The effects of including beta-delayed neutron emission on r-process yield is studied. The role of Coulomb interactions in NSE abundances is shown to be significant, supporting previous findings. A comparative analysis was undertaken during the development of r-Java 2.0 whereby we reproduced the results found in the literature from three other r-process codes. This code is capable of simulating the physical environment of the high-entropy wind around a proto-neutron star, the ejecta from a neutron star merger, or the relativistic ejecta from a quark nova. Likewise the users of r-Java 2.0 are given the freedom to define a custom environment. This software provides a platform for comparing proposed r-process sites.

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

2014-08-01

272

Icosahedral short-range order in amorphous Cu80Si20 by ab initio molecular dynamics simulation study  

SciTech Connect

Short-range order in liquid and amorphous structures of Cu80Si20 is studied by ab initio molecular dynamics simulations. We performed the simulations at 1140 and 300 K respectively to investigate the local structure change from liquid to amorphous. The result of structure factor in comparison with experimental data indicates that our simulation of amorphous Cu80Si20 is reliable. By using the bond-angle distribution function, Honeycutt–Andersen index, Voronoi tessellation method, and the atomistic cluster alignment method, the icosahedral short-range order in the system is revealed. Strong Cu–Si interaction was also observed.

Wu, S.; Kramer, Matthew J.; Fang, Xiaowei; Wang, Shy-Guey; Wang, Cai-Zhuang; Ho, Kai-Ming; Ding, Z.J.; Chen, L.Y.

2012-04-26

273

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)

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.

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

2010-07-01

274

New features in OSIRIS 2.0  

NASA Astrophysics Data System (ADS)

OSIRIS 2.0 [1] is a state of the art, fully relativistic massively parallel particle in cell code, that is widely used in kinetic plasma modeling for many astrophysical and laboratory scenarios. We report on the new developments done in the code, focusing on the new high performance vector SIMD code (Altivec/SSE3) for single precision calculations, detailing performance and floating point efficiency, and also parallel I/O for diagnostics, allowing for higher performance and scalability on HPC systems. We will also describe the new numerical precision features in the code, and we will also present the new algorithms incorporated into the code, in terms of field solver (4^th order Yee solver, etc.), new filtering techniques, perfectly matched layers (PML) boundary conditions, and boosted frame simulations. Finally, we also report on a new diagnostic tool to calculate the radiation produced with wavelengths below the simulation grid resolution. [4pt] [1] R. A. Fonseca et al., LNCS 2331, 342, (2002)

Fonseca, R. A.; Martins, S. F.; Abreu, P.; Martins, J.; Fiúza, F.; Vieira, J.; Silva, L. O.; Decyk, V.; Tsung, F.; Tonge, J.; Mori, W. B.

2009-11-01

275

ViennaRNA Package 2.0  

PubMed Central

Background Secondary structure forms an important intermediate level of description of nucleic acids that encapsulates the dominating part of the folding energy, is often well conserved in evolution, and is routinely used as a basis to explain experimental findings. Based on carefully measured thermodynamic parameters, exact dynamic programming algorithms can be used to compute ground states, base pairing probabilities, as well as thermodynamic properties. Results The ViennaRNA Package has been a widely used compilation of RNA secondary structure related computer programs for nearly two decades. Major changes in the structure of the standard energy model, the Turner 2004 parameters, the pervasive use of multi-core CPUs, and an increasing number of algorithmic variants prompted a major technical overhaul of both the underlying RNAlib and the interactive user programs. New features include an expanded repertoire of tools to assess RNA-RNA interactions and restricted ensembles of structures, additional output information such as centroid structures and maximum expected accuracy structures derived from base pairing probabilities, or z-scores for locally stable secondary structures, and support for input in fasta format. Updates were implemented without compromising the computational efficiency of the core algorithms and ensuring compatibility with earlier versions. Conclusions The ViennaRNA Package 2.0, supporting concurrent computations via OpenMP, can be downloaded from http://www.tbi.univie.ac.at/RNA. PMID:22115189

2011-01-01

276

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

Code of Federal Regulations, 2014 CFR

...adjusted gross income amount together with your tax filing status to determine the amount of your income-related monthly...income ranges for individuals with a Federal tax filing status of single, head of household, qualifying widow(er)...

2014-04-01

277

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

Code of Federal Regulations, 2013 CFR

...adjusted gross income amount together with your tax filing status to determine the amount of your income-related monthly...income ranges for individuals with a Federal tax filing status of single, head of household, qualifying widow(er)...

2013-04-01

278

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

Code of Federal Regulations, 2014 CFR

...adjusted gross income amount together with your tax filing status to determine the amount of your income-related monthly...income ranges for individuals with a Federal tax filing status of single, head of household, qualifying widow(er)...

2014-04-01

279

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

Code of Federal Regulations, 2011 CFR

...adjusted gross income amount together with your tax filing status to determine the amount of your income-related monthly...income ranges for individuals with a Federal tax filing status of single, head of household, qualifying widow(er)...

2011-04-01

280

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

Code of Federal Regulations, 2011 CFR

...adjusted gross income amount together with your tax filing status to determine the amount of your income-related monthly...income ranges for individuals with a Federal tax filing status of single, head of household, qualifying widow(er)...

2011-04-01

281

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

Code of Federal Regulations, 2010 CFR

...adjusted gross income amount together with your tax filing status to determine the amount of your income-related monthly...income ranges for individuals with a Federal tax filing status of single, head of household, qualifying widow(er)...

2010-04-01

282

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

Code of Federal Regulations, 2013 CFR

...adjusted gross income amount together with your tax filing status to determine the amount of your income-related monthly...income ranges for individuals with a Federal tax filing status of single, head of household, qualifying widow(er)...

2013-04-01

283

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

Code of Federal Regulations, 2012 CFR

...adjusted gross income amount together with your tax filing status to determine the amount of your income-related monthly...income ranges for individuals with a Federal tax filing status of single, head of household, qualifying widow(er)...

2012-04-01

284

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

Code of Federal Regulations, 2012 CFR

...adjusted gross income amount together with your tax filing status to determine the amount of your income-related monthly...income ranges for individuals with a Federal tax filing status of single, head of household, qualifying widow(er)...

2012-04-01

285

Solar Advisor Model User Guide for Version 2.0  

SciTech Connect

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.

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

2008-08-01

286

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

287

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

288

Linear attenuation coefficients of tissues from 1 keV to 150 keV  

NASA Astrophysics Data System (ADS)

The linear attenuation coefficients and three interaction processes have been computed for liver, kidney, muscle, fat and for a range of x-ray energies from 1 keV to 150 keV. Molecular photoelectric absorption cross sections were calculated from atomic cross section data. Total coherent (Rayleigh) and incoherent (Compton) scattering cross sections were obtained by numerical integration over combinations of F2m(x) with the Thomson formula and Sm(x) with the Klein-Nishina formula, respectively. For the coherent (Rayleigh) scattering cross section calculations, molecular form factors were obtained from recent experimental data in the literature for values of x<1 Å-1 and from the relativistic modified atomic form factors for values of x?1 Å-1. With the inclusion of molecular interference effects in the coherent (Rayleigh) scattering, more accurate knowledge of the scatter from these tissues will be provided. The number of elements involved in tissue composition is 5 for liver, 47 for kidney, 44 for muscle and 3 for fat. The results are compared with previously published experimental and theoretical linear attenuation coefficients. In general, good agreement is obtained. The molecular form factors and scattering functions and cross sections are incorporated into a Monte Carlo program. The energy distributions of x-ray photons scattered from tissues have been simulated and the results are presented.

Böke, Aysun

2014-09-01

289

Session 2: Modelling air pollution across a range of scales  

E-print Network

Session 2: Modelling air pollution across a range of scales Ruth Doherty, Massimo Vieno, Ian Mac) EMEP2009 (less complex) Observations Modelling regional air pollution #12;Nested regions: 50 to 5 to 1 km2 O3 concentration (ppb) NO2 concentration (µg m-3) #12;Modelling Urban air pollution Regional

290

The Warburg effect version 2.0  

PubMed Central

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

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

2013-01-01

291

r-Java 2.0: the nuclear physics  

E-print Network

[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...

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

2014-01-01

292

GEM Building Taxonomy (Version 2.0)  

USGS Publications Warehouse

/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

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

2013-01-01

293

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

E-print Network

Analysis of RHESSI 3--10 keV spectra for 27 solar flares is reported. This energy range includes thermal free--free and free--bound continuum and two line features, at 6.7keV and 8keV, principally due to highly ionized iron (Fe). We used the continuum and the flux in the so-called Fe-line feature at 6.7keV to derive the electron temperature T_e, the emission measure, and the Fe-line equivalent width as functions of time in each flare. The Fe/H abundance ratio in each flare is derived from the Fe-line equivalent width as a function of T_e. To minimize instrumental problems with high count rates and effects associated with multi-temperature and nonthermal spectral components, spectra are presented mostly during the flare decay phase, when the emission measure and temperature were smoothly varying. We found flare Fe/H abundance ratios that are consistent with the coronal abundance of Fe (i.e. 4 times the photospheric abundance) to within 20% for at least 17 of the 27 flares; for 7 flares, the Fe/H abundance ratio is possibly higher by up to a factor of 2. We find evidence that the Fe XXV ion fractions are less than the theoretically predicted values by up to 60% at T_e=25 MK appear to be displaced from the most recent theoretical values by between 1 and 3 MK.

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

2006-07-13

294

Exploring Library 2.0 on the Social Web  

ERIC Educational Resources Information Center

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

Brantley, John S.

2010-01-01

295

A pilot study in using web 2.0 to aid academic writing skills  

Microsoft Academic Search

Today a wide range of Web 2.0 applications (such as Facebook, Twitter, Blogs, RSS, Podcasts and Wikis) are giving new challenges and opportunities in teaching and learning. The work described here concerns a pilot study to investigate the acceptability and effectiveness of using web 2.0 as an aid to learning. The work focuses on a university course on academic writing

Azamjon Tulaboev; Alan Oxley

2010-01-01

296

QuakeSim 2.0  

NASA Technical Reports Server (NTRS)

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.

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

297

Discovery of Water Maser Emission in Five AGN and a Possible Correlation Between Water Maser and Nuclear 2-10 keV Luminosities  

E-print Network

We report the discovery of water maser emission in five active galactic nuclei (AGN) with the 100-m Green Bank Telescope (GBT). The positions of the newly discovered masers, measured with the VLA, are consistent with the optical positions of the host nuclei to within 1 sigma (0.3 arcsec radio and 1.3 arcsec optical) and most likely mark the locations of the embedded central engines. The spectra of three sources, 2MASX J08362280+3327383, NGC 6264, and UGC 09618 NED02, display the characteristic spectral signature of emission from an edge-on accretion disk with maximum orbital velocity of ~700, ~800, and ~1300 km s^-1, respectively. We also present a GBT spectrum of a previously known source MRK 0034 and interpret the narrow Doppler components reported here as indirect evidence that the emission originates in an edge-on accretion disk with orbital velocity of ~500 km s^-1. We obtained a detection rate of 12 percent (5 out of 41) among Seyfert 2 and LINER systems with 10000 km s^-1 water masers with available hard X-ray data, we report a possible relationship between unabsorbed X-ray luminosity (2-10 keV) and total isotropic water maser luminosity, L_{2-10} proportional to L_{H2O}^{0.5+-0.1}, consistent with the model proposed by Neufeld and Maloney in which X-ray irradiation and heating of molecular accretion disk gas by the central engine excites the maser emission.

Paul T. Kondratko; Lincoln J. Greenhill; James M. Moran

2006-10-03

298

Discovery of Water Maser Emission in Five AGNs and a Possible Correlation Between Water Maser and Nuclear 2-10 keV Luminosities  

NASA Astrophysics Data System (ADS)

We report the discovery of water maser emission in five active galactic nuclei (AGNs) with the 100 m Green Bank Telescope (GBT). The positions of the newly discovered masers, measured with the VLA, are consistent with the optical positions of the host nuclei to within 1 ? (0.3" radio and 1.3" optical) and most likely mark the locations of the embedded central engines. The spectra of three sources, 2MASX J08362280+3327383, NGC 6264, and UGC 09618 NED02, display the characteristic spectral signature of emission from an edge-on accretion disk with maximum orbital velocity of ~700, ~800, and ~1300 km s-1, respectively. We also present a GBT spectrum of a previously known source, Mrk 0034, and interpret the narrow Doppler components reported here as indirect evidence that the emission originates in an edge-on accretion disk with orbital velocity of ~500 km s-1. We obtained a detection rate of 12% (5 out of 41) among Seyfert 2 and LINER systems with 10,000 km s-12-10 keV) and total isotropic water maser luminosity, L2-10~L0.5+/-0.1H2O, consistent with the model proposed by Neufeld and Maloney, in which X-ray irradiation and heating of molecular accretion disk gas by the central engine excites the maser emission.

Kondratko, Paul T.; Greenhill, Lincoln J.; Moran, James M.

2006-11-01

299

Understanding the pedagogy Web 2.0 supports: The presentation of a Web 2.0 pedagogical model  

Microsoft Academic Search

This paper explores the concept of Web 2.0 and provides an overview of three types of Web 2.0 tools currently used in education today, namely, wikis, blogs and online forums. The paper also presents the results of a systematic literature review on Web 2.0 in education, the findings of which revealed a lack of Web 2.0 pedagogical models in the

Gavin J Baxter; Thomas M Connolly; Mark H Stansfield; Carole Gould; Nikolina Tsvetkova; Rumyana Kusheva; Bistra Stoimenova; Rositsa Penkova; Mirena Legurska; Neli Dimitrova

2011-01-01

300

Reaction mechanisms in the system {sup 20}Ne+{sup 165}Ho: Measurement and analysis of forward recoil range distributions  

SciTech Connect

Keeping in view the study of complete and incomplete fusion of heavy ions with a target, the forward recoil range distributions of several evaporation residues produced at 164 MeV {sup 20}Ne-ion beam energy have been measured for the system {sup 20}Ne+{sup 165}Ho. The recoil catcher activation technique followed by off-line gamma spectroscopy has been employed. Measured forward recoil range distributions of these evaporation residues show evidence of several incomplete fusion channels in addition to complete fusion. The entire and partial linear momentum transfers inferred from these recoil range distributions were used to identify the evaporation residues formed by complete and incomplete fusion mechanisms. The results indicate the occurrence of incomplete fusion involving the breakup of {sup 20}Ne into {sup 4}He+{sup 16}O and/or {sup 8}Be+{sup 12}C followed by fusion of one of the fragments with target nucleus {sup 165}Ho. Complete and incomplete fusion reaction channels have been identified in the production of various evaporation residues and an attempt has been made to separate out relative contributions of complete and incomplete fusion components from the analysis of the measured recoil range distribution data. The total contribution of complete and incomplete fusion channels has also been estimated.

Singh, D.; Ali, R.; Ansari, M. Afzal [Department of Physics, Aligarh Muslim University, Aligarh-202002 (India); Rashid, M. H.; Guin, R.; Das, S. K. [Variable Energy Cyclotron Centre, 1/AF Bidhan Nagar, Kolkata-700064 (India)

2009-05-15

301

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

NASA Technical Reports Server (NTRS)

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

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

1972-01-01

302

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

SciTech Connect

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.

Furnish, M.D.

1994-12-01

303

Climate and habitat availability determine 20th century changes in a butterfly's range margin  

PubMed Central

Evidence of anthropogenic global climate change is accumulating, but its potential consequences for insect distributions have received little attention. We use a 'climate response surface' model to investigate distribution changes at the northern margin of the speckled wood butterfly, Pararge aegeria. We relate its current European distribution to a combination of three bioclimatic variables. We document that P. aegeria has expanded its northern margin substantially since 1940, that changes in this species' distribution over the past 100 years are likely to have been due to climate change, and that P. aegeria will have the potential to shift its range margin substantially northwards under predicted future climate change. At current rates of expansion, this species could potentially colonize all newly available climatically suitable habitat in the UK over the next 50 years or more. However, fragmentation of habitats can affect colonization, and we show that availability of habitat may be constraining range expansion of this species at its northern margin in the UK. These lag effects may be even more pronounced in less-mobile species inhabiting more fragmented landscapes, and highlight how habitat distribution will be crucial in predicting species' responses to future climate change.

Hill, J. K.; Thomas, C. D.; Huntley, B.

1999-01-01

304

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

PubMed Central

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

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

2013-01-01

305

Wave-Particle Interactions near ? He + Observed on GEOS 1 and 2, 1. Propagation of Ion Cyclotron Waves in He + Rich Plasma  

Microsoft Academic Search

The GEOS 1 and 2 spacecraft contain a set of particle and wave detectors which allow for a very comprehensive study of wave-particle interactions occurring within the equatorial region of the magnetosphere. This paper is devoted to interactions involving protons in the energy range 20 keV to 300 keV and ULF waves with frequencies below the proton gyrofrequency. It is

D. T. Young; S. Perraut; A. Roux; C. de Villedary; R. Gendrin; A. Korth; G. Kremser; D. Jones

1981-01-01

306

NIST Calibration Uncertainties of Liquid-in-Glass Thermometers over the Range from -20 °C to 400 °C  

NASA Astrophysics Data System (ADS)

The National Institute of Standards and Technology (NIST) Industrial Thermometer Calibration Laboratory (ITCL) is responsible for calibrating several different types of industrial thermometers. One of those types is the liquid-in-glass (LiG) thermometer, which includes both mercury (partial and total immersion) and organic (total immersion) filled models. Over the past two years, improvements in both calibration equipment and software used in the ITCL has led to a new assessment of the uncertainties assigned to the calibration of LiG thermometers covering the temperature range from -20 °C to 400 °C. In total, eighteen thermometers from three different manufacturers, six of which are mercury-filled partial immersion, twelve of which are mercury-filled total immersion, and two of which are organic-filled total immersion models, were used for the determination of LiG thermometer calibration uncertainties over the range from -20 °C to 400 °C in the NIST ITCL.

Vaughn, C. D.; Strouse, G. F.

2003-09-01

307

Dielectric Dispersion Study of Poly(vinyl Pyrrolidone)–Polar Solvent Solutions in the Frequency Range 20 Hz–1 MHz  

Microsoft Academic Search

Influence of polar solvents environment and polymer concentrations on the electrical properties (complex dielectric constant, ac electrical conductivity, complex electric modulus and complex impedance) of the solutions of poly(vinyl pyrrolidone) (PVP) in polar solvents, namely water, ethyl alcohol, ethylene glycol, diethylene glycol, poly(ethylene glycol), glycerol, dimethyl sulfoxide and dimethyl formamide, have been investigated in the frequency range 20 Hz–1 MHz at 25°C.

R. J. Sengwa; Sonu Sankhla

2007-01-01

308

Web 2.0: From a Buzzword to Mainstream Web Reality  

Microsoft Academic Search

\\u000a Since 2006, everything has its Release 2, Version 0, abbreviated “2.0,” e.g., Silicon Valley 2.0, Family 2.0, Gadgets 2.0,\\u000a Pub 2.0, Jobs 2.0, Health 2.0, Entertainment 2.0, Business 2.0, Music 2.0, Enterprise 2.0, Marketing 2.0, Law 2.0, Education\\u000a 2.0, etc. All of this is a consequence of the term “Web 2.0” which was created at O’Reilly Media. But what is

Gottfried Vossen

309

Cross section measurements of the 10B(p ,?)11C reaction between 2.0 and 6.0 MeV  

NASA Astrophysics Data System (ADS)

The total cross section of the 10B(p,?)11C reaction has been measured for bombarding proton energies between 2.0 and 6.0 MeV in 500 keV steps for the first time. This reaction is important for potential next-generation boron fueled nuclear reactors. The total cross section was measured by activating a 10B target with protons and, after stopping the beam, detecting the 511 keV ? rays emitted from the ?+ decay of 11C, using two LaBr3:Ce detectors. In addition to the total cross sections, astrophysical S factors were also calculated at each energy.

Kafkarkou, A.; Ahmed, M. W.; Kendellen, D. P.; Mazumdar, I.; Mueller, J. M.; Myers, L. S.; Sikora, M. H.; Weller, H. R.; Zimmerman, W. R.

2014-01-01

310

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)

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.

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

1985-01-01

311

No 17 keV neutrino: Admixture <0.073% (95% C.L.)  

NASA Astrophysics Data System (ADS)

To solve the controversial issue concerning the possible existence of a 17 keV neutrino with a 1% admixture in nuclear ? decay, we searched directly for any evidence of a production-threshold effect. The 63Ni ? spectrum was measured with a magnetic spectrometer, with very high statistics along with a fine energy scan over a narrow energy region around the expected threshold. The obtained mixing strength was ||U||2=[-0.011+/-0.033(stat)+/-0.030(syst)]%, very consistent with zero, and decisively excluding the existence of a 17 keV neutrino admixing at the 1% level with the electron neutrino. The corresponding upper limit was set at ||U||2<0.073% (95% C.L.). A new limit was also obtained for a wider mass range: ||U||2<0.15% (95% C.L.) for 10.5 to 25.0 keV neutrinos.

Ohshima, T.; Sakamoto, H.; Sato, T.; Shirai, J.; Tsukamoto, T.; Sugaya, Y.; Takahashi, K.; Suzuki, T.; Rosenfeld, C.; Wilson, S.; Ueno, K.; Yonezawa, Y.; Kawakami, H.; Kato, S.; Shibata, S.; Ukai, K.

1993-06-01

312

Structural basis for receptor sharing and activation by interleukin-20 receptor-2 (IL-20R2) binding cytokines.  

PubMed

Interleukin 20 (IL-20) is a pleotropic IL-10 family cytokine that protects epithelial surfaces from pathogens. However, dysregulated IL-20 signaling is implicated in several human pathologies including psoriasis, rheumatoid arthritis, atherosclerosis, and osteoporosis. IL-20, and related cytokines IL-19 and IL-24, designated IL-20 subfamily cytokines (IL-20SFCs), induce cellular responses through an IL-20R1/IL-20R2 (type I) receptor heterodimer, whereas IL-20 and IL-24 also signal through the IL-22R1/IL-20R2 (type II) receptor complex. The crystal structure of the IL-20/IL-20R1/IL-20R2 complex reveals how type I and II complexes discriminate cognate from noncognate ligands. The structure also defines how the receptor-cytokine interfaces are affinity tuned to allow distinct signaling through a receptor complex shared by three different ligands. Our results provide unique insights into the complexity of IL-20SFC signaling that may be critical in the design of mechanistic-based inhibitors of IL-20SFC-mediated inflammatory disease. PMID:22802649

Logsdon, Naomi J; Deshpande, Ashlesha; Harris, Bethany D; Rajashankar, Kanagalaghatta R; Walter, Mark R

2012-07-31

313

46 CFR 54.20-2 - Fabrication for hazardous materials (replaces UW-2(a)).  

Code of Federal Regulations, 2010 CFR

...hazardous materials (replaces UW-2(a)). 54.20-2 Section 54.20-2 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... PRESSURE VESSELS Fabrication by Welding § 54.20-2 Fabrication for hazardous materials (replaces...

2010-10-01

314

38 CFR 20.2 - Rule 2. Procedure in absence of specific Rule of Practice.  

Code of Federal Regulations, 2010 CFR

...Procedure in absence of specific Rule of Practice. 20.2 Section 20.2 Pensions, Bonuses, and Veterans' Relief DEPARTMENT...VETERANS' APPEALS: RULES OF PRACTICE General § 20.2 Rule 2. Procedure in absence of specific Rule...

2010-07-01

315

Dielectric study of allyl chloride with 2-butanol in microwave frequency range  

NASA Astrophysics Data System (ADS)

Dielectric measurement on binary mixtures of Allyl chloride (AC) with 2-butanol have been carried out over the entire concentration range using Time Domain Reflectometry (TDR) technique at 283.15K in the microwave frequency range of 10 MHz to 20 GHz. The static dielectric constant, relaxation time, density, excess static dielectric constant, excess inverse relaxation time, Bruggeman factor, excess molar volume of binary mixtures over entire concentration range were determined to explore the effect hetero molecular interaction. Excess parameters are fitted to Redlich-Kister equation.

Maharolkar, A. P.; Sudake, Y. S.; Kamble, S. P.; Murugkar, A. G.; Patil, S. S.; Khirade, P. W.

2013-06-01

316

Measurements of proton induced ?-ray emission cross sections on MgF2 target in the energy range 1.95-3.05 MeV  

NASA Astrophysics Data System (ADS)

In this work we present differential cross sections for ?-ray emission from the reactions 19F(p,p??)19F (E? = 110, 197, 1236 and 1349 + 1357 keV), 24Mg(p,p??)24Mg (E? = 1369 keV) and 25Mg(p,p??)25Mg (E? = 390, 585 and 975 keV). Differential cross sections were measured for proton energies from 1.95 to 3.05 MeV with a 15 keV step and beam energy resolution of 0.06%. Thin reference standard, 54.1 ?g/cm2 of MgF2 deposited on thin Mylar foil with additionally evaporated 4 nm Au layer, was used as a target. The ?-rays were detected by a 20% relative efficiency HPGe detector placed at an angle of 135° with respect to the beam direction, while the backscattered protons were collected using silicon surface barrier detector placed at the scattering angle of 165°. Obtained cross sections were compared with the previously measured data available from the literature.

Zamboni, I.; Siketi?, Z.; Jakši?, M.; Bogdanovi? Radovi?, I.

2015-01-01

317

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

NASA Astrophysics Data System (ADS)

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

Mohan, Harsh; Jain, Arvind Kumar; Kaur, Mandeep; Singh, Parjit S.; Sharma, Sunita

2014-08-01

318

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

319

(H2O)20 Water Clusters at Finite Temperatures  

NASA Astrophysics Data System (ADS)

We have performed an exhaustive study of energetics of (H2O)20 clusters. Our goal is to study the role that various free-energy terms play in this popular model system and see their effects on the distribution of the (H2O)20 clusters and in the infrared spectrum at finite temperatures. In more detail, we have studied the electronic ground-state structure energy and its long-range correlation (dispersion) part, vibrational zero-point corrections, vibrational entropy, and proton configurational entropy. Our results indicate a delicate competition between the energy terms; polyhedral water clusters are destabilized by dispersion interaction, while vibrational terms (zero-point and entropic) together with proton disorder entropy favor them against compact structural motifs, such as the pentagonal edge- or face-sharing prisms. Apart from small water clusters, our results can be used to understand the influence of these energy terms in water/ice systems in general. We have also developed energy expressions as a function of both earlier proposed and novel hydrogen-bond connectivity parameters for prismatic water clusters.

Parkkinen, P.; Riikonen, S.; Halonen, L.

2013-10-01

320

(H2O)20 water clusters at finite temperatures.  

PubMed

We have performed an exhaustive study of energetics of (H2O)20 clusters. Our goal is to study the role that various free-energy terms play in this popular model system and see their effects on the distribution of the (H2O)20 clusters and in the infrared spectrum at finite temperatures. In more detail, we have studied the electronic ground-state structure energy and its long-range correlation (dispersion) part, vibrational zero-point corrections, vibrational entropy, and proton configurational entropy. Our results indicate a delicate competition between the energy terms; polyhedral water clusters are destabilized by dispersion interaction, while vibrational terms (zero-point and entropic) together with proton disorder entropy favor them against compact structural motifs, such as the pentagonal edge- or face-sharing prisms. Apart from small water clusters, our results can be used to understand the influence of these energy terms in water/ice systems in general. We have also developed energy expressions as a function of both earlier proposed and novel hydrogen-bond connectivity parameters for prismatic water clusters. PMID:23731161

Parkkinen, P; Riikonen, S; Halonen, L

2013-10-01

321

Prevention 2.0: targeting cyberbullying @ school.  

PubMed

Although cyberbullying is characterized by worrying prevalence rates and associated with a broad range of detrimental consequences, there is a lack of scientifically based and evaluated preventive strategies. Therefore, the present study introduces a theory-based cyberbullying prevention program (Media Heroes; German original: Medienhelden) and evaluates its effectiveness. In a pretest-posttest design (9-month interval), schools were asked to randomly assign their participating classes to either control or intervention group. Longitudinal data were available from 593 middle school students (M Age?=?13.3 years, 53 % girls) out of 35 classes, who provided information on cyberbullying behavior as well as socio-demographic and psychosocial variables. While the present results revealed worrying prevalence rates of cyberbullying in middle school, multilevel analyses clearly demonstrate the program's effectiveness in reducing cyberbullying behavior within intervention classes in contrast to classes of the control group. Hence, this study presents a promising program which evidentially prevents cyberbullying in schools. PMID:24122481

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

2014-12-01

322

Evolution des Internets als Wegbereiter von Web 2.0  

Microsoft Academic Search

\\u000a In zahlreichen Büchern und Artikeln, die in den vergangenen zwei Jahren rund um den Begriff Web 2.0 veröffentlicht wurden, gab es unterschiedliche Ansätze, das Phänomen Web 2.0 zu definieren. Letztendlich ist aber Web\\u000a 2.0 ein Begriff unter dem sich verschiedene technologische, soziale, aber auch ökonomische Entwicklungen im Internet ansiedeln.\\u000a Daher ist es so gut wie unmöglich, eine klare und abgrenzende

Christian M. Messerschmidt; Sven C. Berger; Bernd Skiera

323

Bringing Mobile Devices to Web 2.0  

Microsoft Academic Search

While the concept of Web 2.0 has been gaining popularity, the mobile devices are also evolving to a potential platform to play an important role in Web 2.0 systems. Even with their limitation such as small screen and diculty of typing a text, mobile devices can provide benets to the Web 2.0 by augmenting user created contents with contextual informa-

Keisuke Nishimoto

324

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

SciTech Connect

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.

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

1996-01-01

325

A possible line feature at 73 keV from the Crab Nebula  

NASA Technical Reports Server (NTRS)

Evidence is reported for a possible line feature at 73 keV from the Crab Nebula. The experiment was conducted with a balloon-borne high-resolution gamma-ray spectrometer on June 10, 1974, over Palestine, Texas. The intensity and the width of the line derived from the fitting of these data are approximately 0.0038 photon per (sq cm-sec) and less than 4.9 keV FWHM, respectively. The line is superposed on a power-law continuum of 11.2 E to the -2.16 photons per (sq cm-keV) in the energy range from 53 to 300 keV, which is consistent with other measurements of the Crab Nebula spectrum.

Ling, J. C.; Mahoney, W. A.; Willett, J. B.; Jacobson, A. S.

1979-01-01

326

Patent Fair Use2.0 Katherine J. Strandburg*  

E-print Network

265 Patent Fair Use2.0 Katherine J. Strandburg* I. Introduction .................................................................................................................266 A. The Noncontextual Focus of Patent Doctrine........................................266 II. Why Patent Fair Use Now

Loudon, Catherine

327

High sensitivity search for a 17 keV neutrino. Negative indication with an upper limit of 0.095%  

NASA Astrophysics Data System (ADS)

We have performed a search for a 17 keV neutrino by looking for a kink in the 63Ni ?-spectrum near the expected energy threshold. Using a large number of events (2.4 × 10 9) accumulated in a narrow energy region with the INS iron-free ??2 ?-spectrometer, we obtain a mixing strength of [1.8±3.3(stat.)±3.3(syst.)]×10 -4, and no indication of the presence of a 17 keV neutrino with the order of 1% mixing. We set an upper limit of 0.095% for the admixture of a neutrino with a mass of 17 keV and of 0.1% with a mass range of 10-24 keV, at the 95% confidence level.

Kawakami, H.; Kato, S.; Oshima, T.; Rosenfeld, C.; Sakamoto, H.; Sato, T.; Shibata, S.; Shirai, J.; Sugaya, Y.; Suzuki, T.; Takahashi, K.; Tsukamoto, T.; Ueno, K.; Ukai, K.; Wilson, S.; Yonezawa, Y.

1992-08-01

328

Fitness Fever and Fitness Fever 2.0 Requirements  

E-print Network

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

Weber, David J.

329

Evaluating HDR photos using Web 2.0 technology  

NASA Astrophysics Data System (ADS)

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.

Qiu, Guoping; Mei, Yujie; Duan, Jiang

2011-01-01

330

The Anima Animation System, Version 2.0  

E-print Network

in the film and game industries. Animation software has become an important Canadian industry, dueThe Anima Animation System, Version 2.0 Danielle Sauer, Jared Gabruch, Cara Gibbs, Howard Hamilton...........................................................................................................2 2. Animation Software

Hamilton, Howard J.

331

Cross Sections and Swarm Coefficients for Nitrogen Ions and Neutrals in N2 and Argon Ions and Neutrals in Ar for Energies from 0.1 eV to 10 keV  

Microsoft Academic Search

Graphical and tabulated data and the associated bibliography are presented for cross sections for elastic, excitation, and ionization collisions of N+, N+2, N, and N2 with N2 and for Ar+ and Ar with Ar for laboratory energies from 0.1 eV to 10 keV. Where appropriate, drift velocities and reaction or excitation coefficients are calculated from the cross sections and recommended

A. V. Phelps

1991-01-01

332

20 CFR 363.2 - Definitions.  

Code of Federal Regulations, 2010 CFR

...AND PROCEDURES GARNISHMENT OF REMUNERATION OF BOARD PERSONNEL § 363.2...which are otherwise payable to an individual, to another party in order to satisfy a legal obligation of such individual to provide child support or...

2010-04-01

333

17 CFR 20.2 - Covered contracts.  

Code of Federal Regulations, 2012 CFR

...CMX Silver. ICE Futures U.S. (“ICUS”) Cocoa. ICUS Coffee C. ICUS Cotton No. 2. ICUS Frozen Concentrated Orange...Brent Financial. NYMEX Central Appalachian Coal. NYMEX Coffee. NYMEX Cotton. NYMEX Crude Oil, Light Sweet....

2012-04-01

334

17 CFR 20.2 - Covered contracts.  

Code of Federal Regulations, 2014 CFR

...CMX Silver. ICE Futures U.S. (“ICUS”) Cocoa. ICUS Coffee C. ICUS Cotton No. 2. ICUS Frozen Concentrated Orange...Brent Financial. NYMEX Central Appalachian Coal. NYMEX Coffee. NYMEX Cotton. NYMEX Crude Oil, Light Sweet....

2014-04-01

335

17 CFR 20.2 - Covered contracts.  

Code of Federal Regulations, 2013 CFR

...CMX Silver. ICE Futures U.S. (“ICUS”) Cocoa. ICUS Coffee C. ICUS Cotton No. 2. ICUS Frozen Concentrated Orange...Brent Financial. NYMEX Central Appalachian Coal. NYMEX Coffee. NYMEX Cotton. NYMEX Crude Oil, Light Sweet....

2013-04-01

336

20 CFR 361.2 - Scope.  

Code of Federal Regulations, 2014 CFR

...ADMINISTRATION, POLICY AND PROCEDURES RECOVERY OF DEBTS OWED TO THE UNITED STATES GOVERNMENT BY GOVERNMENT EMPLOYEES § 361.2 Scope...5 U.S.C. 5514 apply in recovering certain debts by administrative offset, except where...

2014-04-01

337

20 CFR 361.2 - Scope.  

Code of Federal Regulations, 2013 CFR

...is explicitly provided for or prohibited by another statute (e.g., travel advances in 5 U.S.C. 5705 and employee training expenses in 5 U.S.C. 4108). (2) Waiver requests and claims to the U.S. General Accounting...

2013-04-01

338

20 CFR 361.2 - Scope.  

Code of Federal Regulations, 2010 CFR

...is explicitly provided for or prohibited by another statute (e.g., travel advances in 5 U.S.C. 5705 and employee training expenses in 5 U.S.C. 4108). (2) Waiver requests and claims to the U.S. General Accounting...

2010-04-01

339

20 CFR 361.2 - Scope.  

Code of Federal Regulations, 2011 CFR

...is explicitly provided for or prohibited by another statute (e.g., travel advances in 5 U.S.C. 5705 and employee training expenses in 5 U.S.C. 4108). (2) Waiver requests and claims to the U.S. General Accounting...

2011-04-01

340

The EUROCALL Review, Volume 20, Number 2  

ERIC Educational Resources Information Center

"The EUROCALL Review" is published online biannually by the European Association for Computer-Assisted Language Learning (EUROCALL). This issue offers regular sections on: (1) up-to-date information on Special Interest Groups; (2) reports on on-going CALL or CALL-related R&D projects in which EUROCALL members participate; (3) reports and reviews…

Gimeno, Ana, Ed.

2012-01-01

341

Theoretical electron impact elastic, ionization and total cross sections for silicon hydrides, SiH x (x = 1, 2, 3, 4) and disilane, Si 2 H 6 from threshold to 5 keV  

Microsoft Academic Search

.  In this article we report comprehensive calculations of \\u000a total elastic (Qel), and total ionization cross sections, (Qion), on \\u000a silicon hydrides SiHx (x = 1–4) and disilane, Si2H6 on electron \\u000a impact at energies from circa threshold to 2000 eV and total (complete) \\u000a cross sections (QT) up to 5 keV. Spherical complex optical potential \\u000a (SCOP) formalism is employed to evaluate Qel and QT. Total

M. Vinodkumar; C. Limbachiya; K. Korot; K. N. Joshipura

2008-01-01

342

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

NASA Astrophysics Data System (ADS)

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.

Karl, N.; Reichel, K.; Chen, H.-T.; Taylor, A. J.; Brener, I.; Benz, A.; Reno, J. L.; Mendis, R.; Mittleman, D. M.

2014-03-01

343

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

SciTech Connect

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.

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

344

LSST Science Book, Version 2.0  

Microsoft Academic Search

A survey that can cover the sky in optical bands over wide fields to faint magnitudes with a fast cadence will enable many of the exciting science opportunities of the next decade. The Large Synoptic Survey Telescope (LSST) will have an effective aperture of 6.7 meters and an imaging camera with field of view of 9.6 deg^2, and will be

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

2009-01-01

345

2001 Mercury Computer Systems, Inc. UML 2.0 Redux for HPECUML 2.0 Redux for HPEC  

E-print Network

© 2001 Mercury Computer Systems, Inc. UML 2.0 Redux for HPECUML 2.0 Redux for HPEC Dr. Jeffrey E. Smith Mercury Computer Systems, Inc. Manfred Koethe 88solutions Corp. High Performance Embedded Computing (HPEC) Conference September 25, 2003 #12;2© 2003 Mercury Computer Systems, Inc. UML Overview

Kepner, Jeremy

346

NASA Taxonomy 2.0 Project Overview  

NASA Technical Reports Server (NTRS)

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.

Dutra, Jayne; Busch, Joseph

2004-01-01

347

Heliospheric Neutral Atom Spectra Between 0.01 and 6 keV fom IBEX  

NASA Technical Reports Server (NTRS)

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.

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

2012-01-01

348

A Framework for Web 2.0 Learning Design  

ERIC Educational Resources Information Center

This paper describes an approach to conceptualising and performing Web 2.0-enabled learning design. Based on the Technological, Pedagogical and Content Knowledge model of educational practice, the approach conceptualises Web 2.0 learning design by relating Anderson and Krathwohl's Taxonomy of Learning, Teaching and Assessing, and different types…

Bower, Matt; Hedberg, John G.; Kuswara, Andreas

2010-01-01

349

Leadership 2.0: Social Media in Advocacy  

ERIC Educational Resources Information Center

Technology is always changing, always improving, and always pushing the envelope for how one works in education. In this increasingly connected age, people have seen rapid growth in social network tools such as Twitter and Facebook. These sites are representative of Web 2.0 resources where users contribute content. Other examples of Web 2.0 sites…

Gonzales, Lisa; Vodicka, Devin; White, John

2011-01-01

350

What You Need to Know about Web 2.0  

ERIC Educational Resources Information Center

Also known as the read/write or participatory Web, Web 2.0 includes such tools as blogs, podcasts, forums, wikis and social networks. It gives users the ability to take in information and create, organize and connect with others interested in the same topics. Web 2.0 is revolutionizing education because students and educators can easily and…

Imperatore, Catherine

2009-01-01

351

Students as Digital Citizens on Web 2.0  

ERIC Educational Resources Information Center

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

Nebel, Michelle; Jamison, Barbara; Bennett, Linda

2009-01-01

352

Culture, Learning Styles, and Web 2.0  

ERIC Educational Resources Information Center

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…

Olaniran, Bolanle A.

2009-01-01

353

Project WET Curriculum and Activity Guide 2.0  

ERIC Educational Resources Information Center

The "Project WET Curriculum and Activity Guide 2.0" continues Project WET's dedication to 21st-century, cutting-edge water education. Now in full color, Guide 2.0 offers new activities on topics such as National Parks and storm water, fully revised and updated activities from the original Guide and the very best activities gathered from all of…

Project WET Foundation, 2011

2011-01-01

354

Web 2.0 Strategy in Libraries and Information Services  

ERIC Educational Resources Information Center

Web 2.0 challenges libraries to change from their predominantly centralised service models with integrated library management systems at the hub. Implementation of Web 2.0 technologies and the accompanying attitudinal shifts will demand reconceptualisation of the nature of library and information service around a dynamic, ever changing, networked,…

Byrne, Alex

2008-01-01

355

Scenarios and Strategies for Web 2.0  

ERIC Educational Resources Information Center

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…

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

2009-01-01

356

Ubiquitous Complete in a Web 2.0 World  

ERIC Educational Resources Information Center

In the third wave of computing, people will interact with multiple computers in multiple ways in every setting. The value of ubiquitous computing is enhanced and reinforced by another trend: the transition to a Web 2.0 world. In a Web 2.0 world, applications and data reside on the Web itself. Schools are not yet approaching a ratio of one…

Bull, Glen; Ferster, Bill

2006-01-01

357

Compete 2.0 Thrive.The Skills Imperative  

E-print Network

States of America #12;Thrive. Compete 2.0 The Skills Imperative Debra van Opstal Senior Vice President trends underpinning future skills challenges and oppor- tunities in the United States. Drawing upon. With the Compete 2.0 Initiative, the Council will set a concrete action agenda to ensure that the United States can

358

Titanium Language Reference Manual Version 2.20  

E-print Network

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

California at Irvine, University of

359

Information Literacy Instruction in the Web 2.0 Library  

ERIC Educational Resources Information Center

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…

Humrickhouse, Elizabeth

2011-01-01

360

Web 2.0 in the Mathematics Classroom  

ERIC Educational Resources Information Center

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,…

McCoy, Leah P.

2014-01-01

361

The 2-79 keV X-Ray Spectrum of the Circinus Galaxy with NuSTAR, XMM-Newton, and Chandra: A Fully Compton-thick Active Galactic Nucleus  

NASA Astrophysics Data System (ADS)

The Circinus galaxy is one of the closest obscured active galactic nuclei (AGNs), making it an ideal target for detailed study. Combining archival Chandra and XMM-Newton data with new NuSTAR observations, we model the 2-79 keV spectrum to constrain the primary AGN continuum and to derive physical parameters for the obscuring material. Chandra's high angular resolution allows a separation of nuclear and off-nuclear galactic emission. In the off-nuclear diffuse emission, we find signatures of strong cold reflection, including high equivalent-width neutral Fe lines. This Compton-scattered off-nuclear emission amounts to 18% of the nuclear flux in the Fe line region, but becomes comparable to the nuclear emission above 30 keV. The new analysis no longer supports a prominent transmitted AGN component in the observed band. We find that the nuclear spectrum is consistent with Compton scattering by an optically thick torus, where the intrinsic spectrum is a power law of photon index ? = 2.2-2.4, the torus has an equatorial column density of N H = (6-10) × 1024 cm-2, and the intrinsic AGN 2-10 keV luminosity is (2.3-5.1) × 1042 erg s-1. These values place Circinus along the same relations as unobscured AGNs in accretion rate versus ? and LX versus L IR phase space. NuSTAR's high sensitivity and low background allow us to study the short timescale variability of Circinus at X-ray energies above 10 keV for the first time. The lack of detected variability favors a Compton-thick absorber, in line with the spectral fitting results.

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

2014-08-01

362

BioCat 2.0  

SciTech Connect

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.

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

363

New Measurement of the Relative Scintillation Efficiency of Xenon Nuclear Recoils Below 10 keV  

E-print Network

Liquid xenon is an important detection medium in direct dark matter experiments, which search for low-energy nuclear recoils produced by the elastic scattering of WIMPs with quarks. The two existing measurements of the relative scintillation efficiency of nuclear recoils below 20 keV lead to inconsistent extrapolations at lower energies. This results in a different energy scale and thus sensitivity reach of liquid xenon dark matter detectors. We report a new measurement of the relative scintillation efficiency below 10 keV performed with a liquid xenon scintillation detector, optimized for maximum light collection. Greater than 95% of the interior surface of this detector was instrumented with photomultiplier tubes, giving a scintillation yield of 19.6 photoelectrons/keV electron equivalent for 122 keV gamma rays. We find that the relative scintillation efficiency for nuclear recoils of 5 keV is 0.14, staying constant around this value up to 10 keV. For higher energy recoils we measure a value around 20%, consistent with previously reported data. In light of this new measurement, the XENON10 experiment's results on spin-independent WIMP-nucleon cross section, which were calculated assuming a constant 0.19 relative scintillation efficiency, change from $8.8\\times10^{-44}$ cm$^2$ to $9.9\\times10^{-44}$ cm$^2$ for WIMPs of mass 100 GeV/c$^2$, and from $4.4\\times10^{-44}$ cm$^2$ to $5.6\\times10^{-44}$ cm$^2$ for WIMPs of mass 30 GeV/c$^2$.

E. Aprile; L. Baudis; B. Choi; K. L. Giboni; K. E. Lim; A. Manalaysay; M. E. Monzani; G. Plante; R. Santorelli; M. Yamashita

2010-05-16

364

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

NASA Technical Reports Server (NTRS)

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 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 Al2O3, the decrease from room temperature to 20 K was of 7 and 15 percent, respectively. For LaAlO3, it decreased by 14 percent, for ZrO2 by 15 percent, and for SiO2 by 2 percent, in the above mentioned temperature range.

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

1989-01-01

365

50 CFR 30.2 - Disposition of surplus range animals.  

Code of Federal Regulations, 2011 CFR

...Disposition of surplus range animals. Disposition shall be...circumstances affecting the animals, their range, or the recipient...circumstances.” Surplus range animals may be disposed of, subject to State and Federal...

2011-10-01

366

50 CFR 30.2 - Disposition of surplus range animals.  

Code of Federal Regulations, 2010 CFR

...Disposition of surplus range animals. Disposition shall be...circumstances affecting the animals, their range, or the recipient...circumstances.” Surplus range animals may be disposed of, subject to State and Federal...

2010-10-01

367

50 CFR 30.2 - Disposition of surplus range animals.  

Code of Federal Regulations, 2014 CFR

...Disposition of surplus range animals. Disposition shall be...circumstances affecting the animals, their range, or the recipient...circumstances.” Surplus range animals may be disposed of, subject to State and Federal...

2014-10-01

368

50 CFR 30.2 - Disposition of surplus range animals.  

Code of Federal Regulations, 2013 CFR

...Disposition of surplus range animals. Disposition shall be...circumstances affecting the animals, their range, or the recipient...circumstances.” Surplus range animals may be disposed of, subject to State and Federal...

2013-10-01

369

50 CFR 30.2 - Disposition of surplus range animals.  

Code of Federal Regulations, 2012 CFR

...Disposition of surplus range animals. Disposition shall be...circumstances affecting the animals, their range, or the recipient...circumstances.” Surplus range animals may be disposed of, subject to State and Federal...

2012-10-01

370

Energy Demand in China (Carbon Cycle 2.0)  

SciTech Connect

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/

Price, Lynn

2010-02-02

371

Carbon Cycle 2.0: Ashok Gadgil: global impact  

SciTech Connect

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/

Ashok Gadgi

2010-02-09

372

Biofuels Science and Facilities (Carbon Cycle 2.0)  

SciTech Connect

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/

Keasling, Jay D

2010-02-04

373

Carbon Cycle 2.0: Ashok Gadgil: global impact  

ScienceCinema

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/

Ashok Gadgi

2010-09-01

374

Biofuels Science and Facilities (Carbon Cycle 2.0)  

ScienceCinema

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/

Keasling, Jay D

2011-06-03

375

Energy Demand in China (Carbon Cycle 2.0)  

ScienceCinema

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/

Price, Lynn

2011-06-08

376

CRICKET V2.0 NETWORKS AND MOBILE SYSTEMS GROUP  

E-print Network

5 5 4 4 3 3 2 2 1 1 D D C C B B A A CRICKET V2.0 NETWORKS AND MOBILE SYSTEMS GROUP CSAIL@MIT LEAD CRICKET RS232 Crossbow Technology 41 Daggett Drive San Jose, CA. 95134 B 1 6Wednesday, October 20, 2004 X A A PCLK PDATA PALE RADIO DATA SPI_SCK SPI_MOSI SPI_MISO CHP_OUT ADC0 (RSSI) RADIO CONTROL CRICKET V2

377

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

PubMed Central

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

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

2012-01-01

378

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

ERIC Educational Resources Information Center

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…

Arya, Harsh Bardhan; Mishra, J. K.

2011-01-01

379

Validation and verification of the OPI 2.0 System  

PubMed Central

Purpose The Ocular Protection Index (OPI) 2.0 System was developed to evaluate ocular surface protection under a natural blink pattern and normal visual conditions. The OPI 2.0 System implements fully automated software algorithms which provide a real-time measurement of corneal exposure (breakup area) for each interblink interval during a 1-minute video. Utilizing this method, the mean breakup area (MBA) and OPI 2.0 (MBA/interblink interval) were calculated and analyzed. The purpose of this study was to verify and validate the OPI 2.0 System for its ability to distinguish between dry eye and normal subjects, and to accurately identify breakup area. Methods In order to verify and validate the OPI 2.0 System, a series of artificial images and a series of still image frames captured during an actual clinical session using fluorescein staining videography were analyzed. Finally, a clinical validation process was completed to determine the effectiveness and clinical relevance of the OPI 2.0 System to differentiate between dry eye and normal subjects. Results Software analysis verification conducted in a set of artificially constructed images and in actual videos both saw minimal error rates. MBA and OPI 2.0 calculations were able to distinguish between the qualifying eyes of dry eye and normal subjects in a statistically significant fashion (P < 0.001 for both outcomes). As expected, dry eye subjects had a higher MBA and OPI 2.0 than normal subjects (0.232, dry eye; 0.040, normal and 0.039, dry eye; 0.006, normal, respectively). Results for the worst eyes and all qualifying analyses based on staining, forced-stare tear film breakup time, and MBA were numerically similar. Conclusion The OPI 2.0 System accurately identifies the degree of breakup area on the cornea and represents an efficient, clinically relevant measurement of the pathophysiology of the ocular surface. PMID:22570541

Abelson, Richard; Lane, Keith J; Rodriguez, John; Johnston, Patrick; Angjeli, Endri; Ousler, George; Montgomery, Douglas

2012-01-01

380

From Web 2.0 to Classroom 3.0  

Microsoft Academic Search

\\u000a Web 2.0 has changed the way people communicate and learn. It has entered into the millennial classroom. This article discusses\\u000a the Web 2.0 phenomenon and how it evolves the traditional classroom into Classroom 3.0 incorporating mobile technology with\\u000a Web 2.0 technology. The impact on the implementation of Classroom 3.0 is also discussed and how it may affect the teaching\\u000a and

Wilfred W. Fong

381

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)

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.

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

382

Version 2.0 Born-Oppenheimer potential for HeH+  

E-print Network

Version 2.0 Born-Oppenheimer potential for HeH+ Krzysztof Pachucki Faculty of Physics, University functions. The Born-Oppenheimer potential for the ground electronic 1+ state is obtained in the range of 0 = 1.463 283 au, the Born-Oppenheimer potential amounts to -2.978 708 310 771(1). Obtained results lay

Pachucki, Krzysztof

383

Nonmagnetic ground state in the cubic compounds PrNi2Cd20 and PrPd2Cd20  

NASA Astrophysics Data System (ADS)

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.

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

2015-03-01

384

42 CFR 2.20 - Relationship to State laws.  

Code of Federal Regulations, 2010 CFR

...Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CONFIDENTIALITY OF ALCOHOL AND DRUG ABUSE PATIENT RECORDS General Provisions § 2.20 Relationship to State laws. The statutes authorizing...

2010-10-01

385

Information management using Web 2.0 technology  

E-print Network

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 ...

Duffy, Juliet (Juliet Maria)

2009-01-01

386

20. Historic American Buildings Survey Alex Bush, Photographer, February 2, ...  

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

20. Historic American Buildings Survey Alex Bush, Photographer, February 2, 1937 DOOR TO WEST HALL, SECOND FLOOR - East Alabama Masonic Female Institute, 205 East South Street, Talladega, Talladega County, AL

387

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

388

50 CFR 20.2 - Relation to other provisions.  

Code of Federal Regulations, 2012 CFR

...WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Introduction § 20.2 Relation to other provisions. (a) Migratory bird permits. The provisions of this part...of this subchapter. (b) Migratory bird hunting stamps. The provisions of...

2012-10-01

389

50 CFR 20.2 - Relation to other provisions.  

Code of Federal Regulations, 2014 CFR

...WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Introduction § 20.2 Relation to other provisions. (a) Migratory bird permits. The provisions of this part...of this subchapter. (b) Migratory bird hunting stamps. The provisions of...

2014-10-01

390

50 CFR 20.2 - Relation to other provisions.  

Code of Federal Regulations, 2013 CFR

...WILDLIFE AND PLANTS (CONTINUED) MIGRATORY BIRD HUNTING Introduction § 20.2 Relation to other provisions. (a) Migratory bird permits. The provisions of this part...of this subchapter. (b) Migratory bird hunting stamps. The provisions of...

2013-10-01

391

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...................................................................................................................8 Essential Service #1: Monitor Environmental and Health Status to Identify and Solve Community

392

2. Historic American Buildings Survey Photocopy from Harpers, vol. 20 ...  

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

2. Historic American Buildings Survey Photocopy from Harpers, vol. 20 1859 Courtesy of Library of Congress NORTH AND EAST FRONTS - United States General Post Office, Between Seventh, Eighth, E, & F Streets, Northwest, Washington, District of Columbia, DC

393

Calculations for the Excitation Functions of Reactions Induced in {sup 63}Cu by Neutrons in the 1- to 20-MeV Energy Range  

SciTech Connect

Calculations for the excitation functions of {sup 63}Cu(n,p){sup 63}Ni, {sup 63}Cu(n,np){sup 62}Ni, {sup 63}Cu(n,{alpha}){sup 60}Co, {sup 63}Cu(n,{alpha}){sup 60m}Co, {sup 63}Cu(n,{alpha}n){sup 59}Co, {sup 63}Cu(n,n'){sup 63}Cu, and {sup 63}Cu(n,2n){sup 62}Cu reactions were carried out using Hauser-Feshbach and preequilibrium reaction theories for neutrons in the 1- to 20-MeV energy range. The results have been compared with reported measurements and standard evaluations.

Gul, K. [Pakistan Institute of Nuclear Science and Technology (Pakistan)

2000-10-15

394

The emerging political economy of Humanity 2.0  

Microsoft Academic Search

“Humanity 2.0” refers to the title of my recent book (Humanity 2.0: What It Means to Be Human Past, Present and Future, Palgrave Macmillan, 2011), in which I present humanity as historically poised to re-negotiate its sense of collective identity. There are at least five reasons for this, which are addressed in this paper: (a) the prominence of digital technology

Steve Fuller

2012-01-01

395

Entrepreneurial marketing and the Web 2.0 interface  

Microsoft Academic Search

Purpose – The paper aims to analyse the relationship between marketing and entrepreneurship. It looks at the way in which Web 2.0 technologies are changing the marketing and entrepreneurial landscapes. Design\\/methodology\\/approach – The paper explores the impact of Web 2.0 social media for entrepreneurial marketing. It looks at social media as a marketing tool and considers the positive and negative

Brian Jones

2010-01-01

396

What Web 2.0 Means to Facilities Professionals  

ERIC Educational Resources Information Center

It's official--the Web is now social. Actually, it has always been social to a degree, but now it's "mostly" social. A lot of terms have been coined or adopted to describe various aspects of this phenomenon--social media, social networking, consumer-generated media (CGM) and Web 2.0. While it is hard to define "exactly" what Web 2.0 is, or when…

Allen, Scott

2008-01-01

397

RadCat 2.0 User Guide.  

SciTech Connect

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

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

398

Traffic metrics and Web 2.0-ness  

Microsoft Academic Search

Purpose – There has been considerable discussion of various aspects of the “Web 2.0” concept in the past several years. However, the Web 2.0 concept as a whole has not been analysed through the lens of the Web 1.0 metrics on which managers rely heavily for planning and evaluation. This paper aims to analyse the relationships among a site's audience

I-Ping Chiang; Chun-Yao Huang; Chien-Wen Huang

2010-01-01

399

Happiness and the Family 2.0 Paradigm  

NASA Astrophysics Data System (ADS)

Does new media technology have the potential to make us happier? This paper explores the influence of new information communication technologies on family life satisfaction while analyzing some of the factors that determine changes in the way we live our lives in the information age. Family 2.0 is the new paradigm of family life and the emergence of Web 2.0 type of applications is at the very core of its existence.

Mocan, Rodica; Racorean, Stefana

400

Diffuse x-ray background spectrum from 3 to 50 keV  

SciTech Connect

The spectrum of the extragalactic diffuse X-ray background has been measured with the GSFC Cosmic X-Ray Experiment on HEAO 1 for regions of the sky away from known point sources and more than 20 /sup 0/ from the galactic plane. A total exposure of 80 m/sup 2/-s-sr is available at present. Free-free emission from an optically thin plasma of 40 +- 5 keV provides an excellent description of the observed spectrum from 3 to 50 keV. This spectral shape is confirmed by measurements from five separate layers of three independent detectors. With an estimated absolute precision of approx.10%, the intensity of the emission at 10 keV is 3.2 keV keV/sup -1/ cm/sup -2/ s/sup -1/ sr/sup -1/, a value consistent with the average of previously reported spectra. No other spectral features, such as iron line emission, are evident. This spectrum is not typical of known extra-galactic objects. A uniform hot intergalactic medium of approximately 36% of the closure density of the universe would produce such a flux, although nonuniform models indicating less total matter are probably more realistic.

Marshall, F.E.; Boldt, E.A.; Holt, S.S.; Miller, R.B.; Mushotzky, R.F.; Rose, L.A.; Rothschild, R.E.; Serlemitsos, P.J.

1980-01-01

401

Measured and calculated differential and total yield cross-section data of ⁵⁸Ni(n,xα) and ⁶³Cu(n,xp) in the neutron energy range from 2.0 to 15.6 MeV  

Microsoft Academic Search

Double-differential (n,xp) and (n,xα) cross-section ratio measurements are performed at the 7-MV Van de Graaff accelerator laboratory for neutron energies between 2.0 and 15.6 MeV. The following reaction rate ratios are measured: ⁵⁸Ni(n,xα) to ²⁷(n,α), ⁵⁸Ni(n,xα) to ⁵⁸Ni(n,p), ⁶³Cu(n,xp) to ²⁷Al(n,α), and ⁶³Cu(n,xp) to ⁵⁸Ni(n,p). Protons or alphas are detected by ÎE-ÎE-E telescopes under 14, 51, 79, 109, and 141

C. Tsabaris; C. Papadopoulos; E. Wattecamps; G. Rollin

1998-01-01

402

SPHY v2.0: Spatial Processes in HYdrology  

NASA Astrophysics Data System (ADS)

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.

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

2015-02-01

403

Health 2.0 and Implications for Nursing Education  

PubMed Central

Over the last 20 years the evolution of web browsers providing easy access to the Internet has initiated a revolution in access to healthcare related information for both healthcare providers and patients. This access has changed both the process used to deliver education and the content of the nursing education curriculum worldwide. Our amazing ability to access information around the world is referred as to Web 1.0. Web 2.0 moves beyond access to a world where users are interactively creating information. With the advent of Health 2.0 we are confronting a second revolution that is challenging all aspects of healthcare including all aspects of nursing. This paper explores the concept of Health 2.0, discusses a conceptual framework approach for integrating Health 2.0 content into the nursing curriculum, outlines examples of key concepts required in today’s nursing curriculum and identifies selected issues arising from the impact of Health 2.0. PMID:24199108

Nelson, Ramona

2012-01-01

404

Month HDD1/ Precip Snow 2" 4" 8" 20" 40"  

E-print Network

Month HDD1/ GDU2/ Precip Snow 2" 4" 8" 20" 40" Jan 10.0 1703.5 0.36 5.4 26.1 27.1 29.2 32.1 - 4355 temperature, growing degree units (GDU), precipitation, snow, and evaporation. Solar radiation based on 1972

Netoff, Theoden

405

CRICKET V2.0 NETWORKS AND MOBILE SYSTEMS GROUP  

E-print Network

5 5 4 4 3 3 2 2 1 1 D D C C B B A A CRICKET V2.0 NETWORKS AND MOBILE SYSTEMS GROUP CSAIL@MIT LEAD DESIGNER: NISSANKA B. PRIYANTHA 6310-0335-01 A MTS450CA CRICKET RS232 Crossbow Technology 41 Daggett Drive

406

Low Cost Solar Energy Conversion (Carbon Cycle 2.0)  

SciTech Connect

Ramamoorthy Ramesh from LBNL's Materials Science Division 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/

Ramesh, Ramamoorthy

2010-02-04

407

Low Cost Solar Energy Conversion (Carbon Cycle 2.0)  

ScienceCinema

Ramamoorthy Ramesh from LBNL's Materials Science Division 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/

Ramesh, Ramamoorthy

2011-06-08

408

Long range intermolecular interactions between the alkali diatomics Na2, K2, and NaK  

NASA Astrophysics Data System (ADS)

Long range interactions between the ground state alkali diatomics Na2-Na2, K2-K2, Na2-K2, and NaK-NaK are examined. Interaction energies are first determined from ab initio calculations at the coupled-cluster with singles, doubles, and perturbative triples [CCSD(T)] level of theory, including counterpoise corrections. Long range energies calculated from diatomic molecular properties (polarizabilities and dipole and quadrupole moments) are then compared with the ab initio energies. A simple asymptotic model potential ELR=Eelec+Edisp+Eind is shown to accurately represent the intermolecular interactions for these systems at long range.

Zemke, Warren T.; Byrd, Jason N.; Michels, H. Harvey; Montgomery, John A.; Stwalley, William C.

2010-06-01

409

Long range intermolecular interactions between the alkali diatomics Na(2), K(2), and NaK.  

PubMed

Long range interactions between the ground state alkali diatomics Na(2)-Na(2), K(2)-K(2), Na(2)-K(2), and NaK-NaK are examined. Interaction energies are first determined from ab initio calculations at the coupled-cluster with singles, doubles, and perturbative triples [CCSD(T)] level of theory, including counterpoise corrections. Long range energies calculated from diatomic molecular properties (polarizabilities and dipole and quadrupole moments) are then compared with the ab initio energies. A simple asymptotic model potential E(LR)=E(elec)+E(disp)+E(ind) is shown to accurately represent the intermolecular interactions for these systems at long range. PMID:20590191

Zemke, Warren T; Byrd, Jason N; Michels, H Harvey; Montgomery, John A; Stwalley, William C

2010-06-28

410

Microionization chamber air-kerma calibration coefficients as a function of photon energy for x-ray spectra in the range of 20-250 kVp relative to {sup 60}Co  

SciTech Connect

Purpose: To investigate the applicability of a wide range of microionization chambers for reference dosimetry measurements in low- and medium-energy x-ray beams. Methods: Measurements were performed with six cylindrical microchamber models, as well as one scanning chamber and two Farmer-type chambers for comparison purposes. Air-kerma calibration coefficients were determined at the University of Wisconsin Accredited Dosimetry Calibration Laboratory for each chamber for a range of low- and medium-energy x-ray beams (20-250 kVp), with effective energies ranging from 11.5 keV to 145 keV, and a {sup 60}Co beam. A low-Z proof-of-concept microchamber was developed and calibrated with and without a high-Z silver epoxy on the collecting electrode. Results: All chambers composed of low-Z materials (Z{<=} 13), including the Farmer-type chambers, the scanning chamber, and the PTW TN31014 and the proof-of-concept microchambers, exhibited air-kerma calibration coefficients with little dependence on the quality of the beam. These chambers typically exhibited variations in calibration coefficients of less than 3% with the beam quality, for medium energy beams. However, variations in air-kerma calibration coefficients of greater than 50% were measured over the range of medium-energy x-ray beams for each of the microchambers containing high-Z collecting electrodes (Z > 13). For these high-Z chambers, which include the Exradin A14SL and A16 chambers, the PTW TN31006 chamber, the IBA CC01 chamber, and the proof-of-concept chamber containing silver, the average variation in air-kerma calibration coefficients between any two calibration beams was nearly 25% over the entire range of beam qualities investigated. Conclusions: Due to the strong energy dependence observed with microchambers containing high-Z components, these chambers may not be suitable dosimeters for kilovoltage x-ray applications, as they do not meet the TG-61 requirements. It is recommended that only microchambers containing low-Z materials (Z{<=} 13) be considered for air-kerma calibrations for reference dosimetry in low- and medium-energy x-ray beams.

Snow, J. R.; Micka, J. A.; DeWerd, L. A. [Department of Medical Physics, University of Wisconsin-Madison, Madison, Wisconsin 53705 (United States)

2013-04-15

411

The development of the Body Morph Assessment version 2.0 (BMA 2.0): Tests of reliability and validity  

PubMed Central

This study tested the psychometric characteristics of the Body Morph Assessment version 2.0 (BMA 2.0). A sample of 563 adults composed of four groups classified by gender and ethnicity (Caucasian men and women and African-American men and women) were studied. Support for the internal consistency and test–retest reliability of the BMA 2.0 was found for both men and women. A study of convergent validity was conducted. The BMA 2.0 was found to have adequate reliability and validity. Norms were established for the BMA 2.0 estimates of current body size (CBS), ideal body size (IBS), and acceptable body size (ABS) for Caucasian and African-American men and women. In summary, the BMA 2.0 is a reliable and valid computerized measure of CBS, IBS, ABS, the CBS–IBS discrepancy (body dissatisfaction), and provides an estimate of over/underestimation of body size as compared to individuals of the same sex and body mass index. PMID:19244002

Stewart, Tiffany M.; Allen, H. Raymond; Han, Hongmei; Williamson, Donald A.

2009-01-01

412

NASA Marshall Engineering Thermosphere Model. 2.0  

NASA Technical Reports Server (NTRS)

This Technical Memorandum describes the NASA Marshall Engineering Thermosphere Model-Version 2.0 (MET-V 2.0) and contains an explanation on the use of the computer program along with an example of the MET-V 2.0 model products. The MET-V 2.0 provides an update to the 1988 version of the model. It provides information on the total mass density, temperature, and individual species number densities for any altitude between 90 and 2,500 km as a function of latitude, longitude, time, and solar and geomagnetic activity. A description is given for use of estimated future 13-mo smoothed solar flux and geomagnetic index values as input to the model. Address technical questions on the MET-V 2.0 and associated computer program to Jerry K. Owens, Spaceflight Experiments Group, Marshall Space Flight Center, Huntsville, AL 35812 (256-961-7576; e-mail Jerry.Owens@msfc.nasa.gov).

Owens, J. K.

2002-01-01

413

The Lagrangian analysis tool LAGRANTO - version 2.0  

NASA Astrophysics Data System (ADS)

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.

Sprenger, M.; Wernli, H.

2015-02-01

414

Carbon Cycle 2.0: Paul Alivisatos: Introduction  

ScienceCinema

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/

Paul Alivisatos

2010-09-01

415

Carbon Cycle 2.0: Paul Alivisatos: Introduction  

SciTech Connect

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/

Paul Alivisatos

2010-02-09

416

Geologic Carbon Sequestration and Biosequestration (Carbon Cycle 2.0)  

SciTech Connect

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/

DePaolo, Don [Director, LBNL Earth Sciences Division] [Director, LBNL Earth Sciences Division

2010-02-03

417

Geologic Carbon Sequestration and Biosequestration (Carbon Cycle 2.0)  

ScienceCinema

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/

DePaolo, Don [Director, LBNL Earth Sciences Division

2011-06-08

418

2.14 2.16 2.18 2.20 hydroxy-apatite  

E-print Network

have contributed to excessive levels of soil P in many parts of the USA, especially in the Mid it is often applied in lime to raise the soil pH. A recent study (Rietra, Hiemstra et al. 20012.14 2.16 2.18 2.20 pH 4 hydroxy-apatite P:Ca 0.3, 0.06 mmol/g P:Ca 1.5, 0.25 mmol/g P:Ca 6, 0

Sparks, Donald L.

419

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

NASA Astrophysics Data System (ADS)

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

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

2004-07-01

420

A facility for measurements of (n,?) cross-sections of a nucleus in the range 0.008? En<20 MeV  

NASA Astrophysics Data System (ADS)

A new measurement system to determine the neutron-capture cross-sections of a nucleus at 0.008? En<20 MeV has been installed at the 4 MV Pelletron accelerator laboratory at the facility of radiation standards at Japan Atomic Energy Agency. The performance of the new system was studied by measuring the neutron-capture reaction cross-section of natPb using pulsed neutrons from 7Li(p,n) 7Be at 12? En?103 keV. Prompt ?-rays from the reaction were detected by means of a highly sensitive anti-Compton NaI(Tl) spectrometer combined with a time-of-flight method. The obtained result demonstrated good sensitivity of the new system to determine the neutron-capture cross-sections of a nucleus at kiloelectron volt neutron energy.

Segawa, M.; Toh, Y.; Harada, H.; Kitatani, F.; Koizumi, M.; Hatsukawa, Y.; Fukahori, T.; Matsue, H.; Oshima, M.; Tanimura, Y.; Tsutsumi, M.; Nagai, Y.

2010-06-01

421

CRICKET V2.0 NETWORKS AND MOBILE SYSTEMS GROUP  

E-print Network

5 4 3 2 1 D D C C B B A A CRICKET V2.0 NETWORKS AND MOBILE SYSTEMS GROUP CSAIL@MIT LEAD DESIGNER: NISSANKA B. PRIYANTHA CROSSPOINT SWITCH MICACONN_TXD0 MICACONN_RXD0 6310-0335-01 A MTS450CA CRICKET RS232

422

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

SciTech Connect

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%.

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

2012-02-08

423

Investigation of the Equivalence of National Dew-Point Temperature Realizations in the -50 °C to + 20 °C Range  

NASA Astrophysics Data System (ADS)

In the field of humidity quantities, the first CIPM key comparison, CCT-K6 is at its end. The corresponding European regional key comparison, EUROMET.T-K6, was completed in early 2008, about 4 years after the starting initial measurements in the project. In total, 24 NMIs from different countries took part in the comparison. This number includes 22 EURAMET countries, and Russia and South Africa. The comparison covered the dew-point temperature range from -50 °C to +20 °C. It was carried out in three parallel loops, each with two chilled mirror hygrometers as transfer standards in each loop. The comparison scheme was designed to ensure high quality results with evenly spread workload for the participants. It is shown that the standard uncertainty due to the long-term instability was smaller than 0.008 °C in all loops. The standard uncertainties due to links between the loops were found to be smaller than 0.025 °C at -50 °C and 0.010 °C elsewhere. Conclusions on the equivalence of the dew-point temperature standards are drawn on the basis of calculated bilateral degrees of equivalence and deviations from the EURAMET comparison reference values (ERV). Taking into account 16 different primary dew-point realizations and 8 secondary realizations, the results demonstrate the equivalence of a large number of laboratories at an uncertainty level that is better than achieved in other multilateral comparisons so far in the humidity field.

Heinonen, Martti; Anagnostou, Miltiadis; Bell, Stephanie; Stevens, Mark; Benyon, Robert; Bergerud, Reidun Anita; Bojkovski, Jovan; Bosma, Rien; Nielsen, Jan; Böse, Norbert; Cromwell, Plunkett; Kartal Dogan, Aliye; Aytekin, Seda; Uytun, Ali; Fernicola, Vito; Flakiewicz, Krzysztof; Blanquart, Bertrand; Hudoklin, Domen; Jacobson, Per; Kentved, Anders; Lóio, Isabel; Mamontov, George; Masarykova, Alexandra; Mitter, Helmut; Mnguni, Regina; Otych, Jan; Steiner, Anton; Szilágyi Zsófia, Nagyné; Zvizdic, Davor

2012-09-01

424

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

SciTech Connect

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.

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

425

Incorporating Web 2.0 Technologies from an Organizational Perspective  

NASA Astrophysics Data System (ADS)

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.

Owens, R.

2009-12-01

426

Collaborative Writing with Web 2.0 Technologies: Education Students' Perceptions  

ERIC Educational Resources Information Center

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…

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

2011-01-01

427

Students as Web 2.0 Authors: Implications for Assessment Design and Conduct  

ERIC Educational Resources Information Center

Students now have at their disposal a range of Web 2.0 authoring forms such as audio and video podcasting, blogging, social bookmarking, social networking, virtual world activities and wiki writing. Many university educators are interested in enabling students to demonstrate their learning by creating content in these forms. However, the design…

Gray, Kathleen; Thompson, Celia; Sheard, Judithe; Clerehan, Rosemary; Hamilton, Margaret

2010-01-01

428

Redefining Vernacular Literacies in the Age of Web 2.0  

ERIC Educational Resources Information Center

In this article, we examine the characteristics of vernacular literacies on Web 2.0, focusing on the writing activities performed on the photo-sharing site Flickr.com. This site provides people with many possibilities for writing, ranging from individual tags to extensive profiles. The study investigates these forms of writing to address questions…

Barton, David; Lee, Carmen K. M.

2012-01-01

429

Learning with Web 2.0: Social Technology and Discursive Psychology  

ERIC Educational Resources Information Center

Recent years have seen the rise of Internet technologies which facilitate activities that are, above all, social and participatory, allowing children and adults to create and share their own content, and to communicate in a wide range of forums. Correspondingly, there has been great popular and expert interest in the potential of Web 2.0…

Friesen, Norm; Lowe, Shannon

2012-01-01

430

UCbase 2.0: ultraconserved sequences database (2014 update).  

PubMed

UCbase 2.0 (http://ucbase.unimore.it) is an update, extension and evolution of UCbase, a Web tool dedicated to the analysis of ultraconserved sequences (UCRs). UCRs are 481 sequences >200 bases sharing 100% identity among human, mouse and rat genomes. They are frequently located in genomic regions known to be involved in cancer or differentially expressed in human leukemias and carcinomas. UCbase 2.0 is a platform-independent Web resource that includes the updated version of the human genome annotation (hg19), information linking disorders to chromosomal coordinates based on the Systematized Nomenclature of Medicine classification, a query tool to search for Single Nucleotide Polymorphisms (SNPs) and a new text box to directly interrogate the database using a MySQL interface. To facilitate the interactive visual interpretation of UCR chromosomal positioning, UCbase 2.0 now includes a graph visualization interface directly linked to UCSC genome browser. Database URL: http://ucbase.unimore.it. PMID:24951797

Lomonaco, Vincenzo; Martoglia, Riccardo; Mandreoli, Federica; Anderlucci, Laura; Emmett, Warren; Bicciato, Silvio; Taccioli, Cristian

2014-01-01

431

Development and application of GASP 2.0  

NASA Technical Reports Server (NTRS)

GASP 2.0 represents a major new release of the computational fluid dynamics code in wide use by the aerospace community. The authors have spent the last two years analyzing the strengths and weaknesses of the previous version of the finite-rate chemistry, Navier Stokes solution algorithm. What has resulted is a completely redesigned computer code that offers two to four times the performance of previous versions while requiring as little as one quarter of the memory requirements. In addition to the improvements in efficiency over the original code, Version 2.0 contains many new features. A brief discussion of the improvements made to GASP, and an application using GASP 2.0 which demonstrates some of the new features are presented.

Mcgrory, W. D.; Huebner, L. D.; Slack, D. C.; Walters, R. W.

1992-01-01

432

MULTI-KEV X-RAY YIELDS FROM HIGH-Z GAS TARGETS FIELDED AT OMEGA  

SciTech Connect

The authors report on modeling of x-ray yield from gas-filled targets shot at the OMEGA laser facility. The OMEGA targets were 1.8 mm long, 1.95 mm in diameter Be cans filled with either a 50:50 Ar:Xe mixture, pure Ar, pure Kr or pure Xe at {approx} 1 atm. The OMEGA experiments heated the gas with 20 kJ of 3{omega} ({approx} 350 nm) laser energy delivered in a 1 ns square pulse. the emitted x-ray flux was monitored with the x-ray diode based DANTE instruments in the sub-keV range. Two-dimensional x-ray images (for energies 3-5 keV) of the targets were recorded with gated x-ray detectors. The x-ray spectra were recorded with the HENWAY crystal spectrometer at OMEGA. Predictions are 2D r-z cylindrical with DCA NLTE atomic physics. Models generally: (1) underpredict the Xe L-shell yields; (2) overpredict the Ar K-shell yields; (3) correctly predict the Xe thermal yields; and (4) greatly underpredict the Ar thermal yields. However, there are spreads within the data, e.g. the DMX Ar K-shell yields are correctly predicted. The predicted thermal yields show strong angular dependence.

Kane, J O; Fournier, K B; May, M J; Colvin, J D; Thomas, C A; Marrs, R E; Compton, S M; Moody, J D; Bond, E J; Davis, J F

2010-11-04

433

Energy-loss scaling in 0. 5--3. 5-keV Ne/sup +/ and Ne collisions with H/sub 2/ and D/sub 2/  

SciTech Connect

Enery losses are measured in Ne/sup +/+D/sub 2/, Ne/sup +/+H/sub 2/, and Ne+D/sub 2/ collisions for beam energies 0.5< or =E< or =3.5 keV and scattering angles theta< or =5 /sup 0/. Rotational and vibrational excitation of the target molecule is found, but the probability of direct electronic excitation is seen to be extremely small. The results indicate that the most probable laboratory energy loss T/sub 0/ for a projectile with mass M/sub p/ scattered by a homonuclear binary molecule with atomic masses M scales so that the quantity f=T/sub 0/M/(M/sub p/Etheta/sup 2/) is a function of the reduced scattering angle tau=Etheta only, as recently predicted theoretically by Sigmund. The function f (tau) is found to be the same for the Ne/sup +/+D/sub 2/ and Ne/sup +/+H/sub 2/ systems, but is strongly dependent on the charge state of the projectile.

Andersen, N.; Vedder, M.; Russek, A.; Pollack, E.

1980-03-01

434

Operation Manual for the TA Instruments DSC Q-100 and Q-20: Temperature Range: -90C 400C  

E-print Network

. In general, good results are obtained when a heating rate of 10-20°C/min is used. For measurement of glass transition temperature a heating rate of 20°C/min (10°C/min-20°C/min are acceptable) is used. For melting, if the glass transition temperature is expected to be 40°C and the heating rate is 20°C/min, the starting

Alpay, S. Pamir

435

Verification and validation of DEPOSITION 2.0  

SciTech Connect

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.

Eadie, W.J.

1994-10-01

436

[Adolescents in Web 2.0: risks and chances ].  

PubMed

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

Salisch, Maria von

2014-01-01

437

mHealth 2.0: Experiences, Possibilities, and Perspectives  

PubMed Central

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

Diamantidis, Clarissa

2014-01-01

438

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

NASA Astrophysics Data System (ADS)

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

Alvarez, Pedro D.; Conlon, Joseph P.; Day, Francesca V.; Marsh, M. C. David; Rummel, Markus

2015-04-01

439

2MASS Asteroid and Comet Survey V2.0  

Microsoft Academic Search

This data set includes J, H, and Ks magnitudes from the Two Micron All-Sky Survey (2MASS) for sources which were positionally associated with asteroids, comets, planets, and planetary satellites. This version includes the 2MASS Extended Mission.

M. V. Sykes; R. Cutri M; M. F. Skrutskie; J. W. Fowler; D. J. Tholen; P. E. Painter; B. Nelson; D. J. Kirkpatrick

2010-01-01

440

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

NASA Technical Reports Server (NTRS)

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.

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

1986-01-01

441

Case ................ 2.10.0 Subrack .......... 2.20.0  

E-print Network

aluminium extrusion and the rear panel made from aluminium sheet are screwed together with profile side extrusion From 5 U two-part 2 1 Front panel Aluminium extrusion clear chromated 3 1 Rear panel Al 2 mm clear Front handle Aluminium extrusion anodised 1 set Fasteners ESA44238 ESA44244 ESA44245 #12;­ 19" chassis 2

Berns, Hans-Gerd

442

The (3He,tf) as a surrogate reaction to determine (n,f) cross sections in the 10 to 20 MeV energy range  

SciTech Connect

The surrogate reaction 238U(3He,tf) is used to determine the 237Np(n,f) cross section indirectly over an equivalent neutron energy range from 10 to 20 MeV. A self-supporting ~;;761 mu g/cm2 metallic 238U foil was bombarded with a 42 MeV 3He2+ beam from the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory (LBNL). Outgoing charged particles and fission fragments were identified using the Silicon Telescope Array for Reaction Studies (STARS), consists of two 140 mu m and one 1000 mu m Micron S2 type silicon detectors. The 237Np(n,f) cross sections, determined indirectly, were compared with the 237Np(n,f) cross section data from direct measurements, the Evaluated Nuclear Data File (ENDF/B-VII.0), and the Japanese Evaluated Nuclear Data Library (JENDL 3.3) and found to closely follow those datasets. Use of the (3He,tf) reaction as a surrogate to extract (n,f) cross section in the 10 to 20 MeV equivalent neutron energy is found to be suitable.

Basunia, M. S.; Clark, R. M.; Goldblum, B. L.; Bernstein, L. A.; Phair, L.; Burke, J. T.; Beausang, C. W.; Bleuel, D. L.; Darakchieva, B.; Dietrich, F. S.; Evtimova, M.; Fallon, P.; Gibelin, J.; Hatarik, R.; Jewett, C. C.; Lesher, S. R.; McMahan, M. A.; Rodriguez-Vieitez, E.; Wiedeking, M.

2009-02-25

443

Web 2.0 and Emerging Technologies in Online Learning  

ERIC Educational Resources Information Center

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,…

Diaz, Veronica

2010-01-01

444

Changing Academic Teaching with Web 2.0 Technologies  

ERIC Educational Resources Information Center

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…

Newland, Barbara; Byles, Linda

2014-01-01

445

Thursday, Nov 20, 2014 12 pm 2pm  

E-print Network

of wearable food and drink intake monitoring system that analyzes human breathing signal for identifying, Privacy Preserving Channel Access for Internet of Things, Accepted, In Press, IEEE Internet of ThingsThursday, Nov 20, 2014 12 pm ­ 2pm EB 3546 DIET MONITORING THROUGH BREATHING SIGNAL ANALYSIS USING

446

Flexibly constructing secure groups in Antigone 2.0  

Microsoft Academic Search

Group communication is increasingly used as a low-cost building block for the development of highly available and survivable services in dynamic environments. However, contemporary frameworks often provide limited facilities for the definition and enforcement of precise security policies. This paper presents the Antigone 2.0 framework that allows the flexible specification and enforcement of group security policies. Enforcement is achieved through

Patrick McDaniel; Atul Prakash; Jim Irrer; Sharad Mittal; Thai-Chuin Thuang

2001-01-01

447

Carbon Cycle 2.0: Robert Cheng and Juan Meza  

ScienceCinema

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.

Robert Cheng and Juan Meza

2010-09-01

448

Carbon Cycle 2.0: Robert Cheng and Juan Meza  

SciTech Connect

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.

Robert Cheng and Juan Meza

2010-02-16

449

Carbon Cycle 2.0: Nitash Balsara: Energy Storage  

SciTech Connect

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.

Nitash Balsara

2010-02-16

450

Carbon Cycle 2.0: Jay Keasling: Biofuels  

SciTech Connect

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.

Jay Keasling

2010-02-16

451

Apacic++ 2.0, A Parton Cascade In C++  

E-print Network

The new version of the parton shower module APACIC++ for the SHERPA event generator framework is presented. It incorporates some features, that are specific for the consistent merging with multi-particle matrix elements at tree-level. This publication also includes some exemplary results and a short description of the upgraded class structure of APACIC++, version 2.0.

F. Krauss; A. Schaelicke; G. Soff

2005-03-09

452

Algebraic Dynamic Programming 2.0 Robert Giegerich  

E-print Network

Algebraic Dynamic Programming 2.0 Robert Giegerich Faculty of Technology and Center of the Algebraic Dynamic Programming framework as it emerged about a decade ago. Here, we present a efficiently, all the dynamic programming machinery must eventually be brought in ­ but no allusion to dynamic

Paris-Sud XI, Université de

453

Updated 2/20/14 Minor in Education  

E-print Network

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

Massachusetts at Amherst, University of

454

Web 2.0 for urban designers & planners  

E-print Network

The author contends that a class of new and emerging participatory Web-based tools, referred to at present as "Web 2.0," can and should be used by urban designers and planners to achieve better results in public participation ...

Wilson, Jase (Jase C.)

2008-01-01

455

Teaching Talented Writers with Web 2.0 Tools  

ERIC Educational Resources Information Center

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.…

Olthouse, Jill M.; Miller, Myriah Tasker

2012-01-01

456

Emerging informal learning 2.0 practices: a preliminary exploration  

Microsoft Academic Search

This paper investigates a specific technology-enhanced learning scenario where formal and informal practices intertwine and contribute to the improvement of individual learning. In particular, we have explored how the students attending a distance learning higher education course (Cognitive Psychology, Uninettuno) have spontaneously started to adopt a set of Web 2.0 resources, commonly used for entertainment and socialization, to organize their

Alessandro Pollini; Leonardo Giusti; Linda Napoletano

2011-01-01

457

Librarians 2.0: Sowing Padi in (the) SEA  

ERIC Educational Resources Information Center

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.…

Chew, Ivan

2009-01-01

458

Bewertung der Informationsqualität im Enterprise 2.0  

NASA Astrophysics Data System (ADS)

Die Entwicklungen zum Web 2.0 haben das World Wide Web (WWW) grundlegend verändert. Nachdem die meisten Nutzer im WWW zunächst "nur" nach Informationen suchten stellen Nutzer inzwischen sehr ausgiebig Informationen über sich selbst oder ihnen vertraute Themen in Blogs und Communities bereit. Facebook und Wikipedia sind zwei prominente Webseiten. Ihre Attraktivität entstammt allein den Informationen, welche die Nutzer selber zur Verfügung stellen.

Ahlheid, Sven; Graefe, Gernot; Krebs, Alexander; Schuster, Dirk

459

Conformally-flat Stäckel spaces of type (2.0)  

NASA Astrophysics Data System (ADS)

Conformally-flat models of space-time that admit privileged coordinate systems allowing complete separation of variables in the Hamilton-Jacobi equation of type (2.0) are considered. An explicit form of metrics for the given spaces is derived in the privileged coordinate systems. Models with dust matter and cosmological constant are constructed for the metrics obtained.

Osetrin, K. E.; Filippov, A. E.

2013-03-01

460

Carbon Cycle 2.0: Jay Keasling: Biofuels  

ScienceCinema

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.

Jay Keasling

2010-09-01

461

Social Work Information Center 2.0: A Case Study  

ERIC Educational Resources Information Center

The social work library at USC provides a case study of an academic library's transition to an information center service model. Analysis of the collection, user community, Web 2.0 applications, and Web usage data demonstrates how the changes facilitated library services and information literacy instruction. (Contains 6 tables and 3 figures.)

Xu, F. Grace

2009-01-01

462

Locating mapped resources in Web 2.0  

Microsoft Academic Search

Mapping mashups are emerging Web 2.0 applica- tions in which data objects such as blogs, photos and videos from different sources are combined and marked in a map using APIs that are released by online mapping solutions such as Google and Yahoo Maps. These objects are typically associated with a set of tags capturing the embedded semantic and a set

Dongxiang Zhang; Beng Chin Ooi; Anthony K. H. Tung

2010-01-01

463

Different Spaces: Staff Development for Web 2.0  

ERIC Educational Resources Information Center

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…

Samarawickrema, Gayani; Benson, Robyn; Brack, Charlotte

2010-01-01

464

Journalism Students, Web 2.0 and the Digital Divide  

ERIC Educational Resources Information Center

The purpose of this study was to find out if students were utilizing Web 2.0 applications. Since the applications in question are often employed by the media industry, the study aspired to find out if students majoring in mass communication and journalism utilized the applications more often than other students. The "digital divide" is a term used…

Green, Mary Elizabeth

2009-01-01

465

Carbon Cycle 2.0: Nitash Balsara: Energy Storage  

ScienceCinema

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.

Nitash Balsara

2010-09-01

466

33 CFR 2.20 - Territorial sea baseline.  

Code of Federal Regulations, 2010 CFR

...Convention on the Law of the Sea (UNCLOS), 21 I.L.M. 1261. Normally, the territorial sea baseline is the mean low water line along the coast of the United States. Note to § 2.20: Charts depicting the territorial sea baseline are...

2010-07-01

467

Web 2.0 for R&R  

ERIC Educational Resources Information Center

Are colleges and universities doing enough to take advantage of Web 2.0 and social networking tools in their recruitment and retention efforts? "Not even close," says Sam Richard, a 23-year-old junior in the College of Public Programs at Arizona State University in Phoenix. Richard is one of six students in ASU's Student Ambassadors for…

Raths, David

2009-01-01

468

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...

469

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...

470

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...

471

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...

472

r-Java 2.0: the astrophysics  

E-print Network

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

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

2014-01-01

473

Conceptualising teachers' professional learning with Web 2.0  

Microsoft Academic Search

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 features of professional learning and the underlying affordances of

Kevin John Burden

2010-01-01

474

AHA! Version 2.0: More Adaptation Flexibility for Authors.  

ERIC Educational Resources Information Center

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…

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

475

Assessing E-Learning 2.0 System Success  

ERIC Educational Resources Information Center

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

Wang, Hei Chia; Chiu, Yi Fang

2011-01-01

476

Conceptualising Teachers' Professional Learning with Web 2.0  

ERIC Educational Resources Information Center

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…

Burden, Kevin John

2010-01-01

477

Pedagogical Lessons from Students' Participation in Web 2.0  

ERIC Educational Resources Information Center

Responses of Vietnamese undergraduate students majoring in English to the integration of a Moodle site during an upper intermediate macro-skill course highlight differences in learner autonomy and expectations. Students' general attitudes towards and participation in this online Web 2.0 environment provide the basis for the research reported in…

Dang, Tan Tin; Robertson, Margaret

2010-01-01

478

PRISM 2.0: A Tool for Probabilistic Model Checking  

Microsoft Academic Search

This paper gives a brief overview of version 2.0 of PRISM, a tool for the automatic formal verification of probabilis- tic systems, and some of the case studies to which it has al- ready been applied. The use of probabilistic modelling for the analysis and verification of computer systems is becoming more and more widespread. Probabilistic model checkingis an auto-

Marta Z. Kwiatkowska; Gethin Norman; David Parker

2004-01-01

479

Web 2.0 Technologies: Applications for Community Colleges  

ERIC Educational Resources Information Center

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

Bajt, Susanne K.

2011-01-01

480

Webquest 2.0: An Instructional Model for Digital Learners  

ERIC Educational Resources Information Center

Teaching and learning tools such as Moodle and Web 2.0 tools are appearing in K-12 classrooms; however, there is a lack of scholarly research to guide the implementation of these tools. The WebQuest model, a widely adopted inquiry-based model for online instruction, has instructional inadequacies and does not make the most of emerging…

Dell, Diana F. Abernathy

2012-01-01