Permeability of flax fibre mats: Numerical and theoretical prediction from 3D X-ray microtomography images

The reaction N14(γ,n)N13 has been studied by irradiating dicyandiamide in the X-ray beam of a 25-Mev betatron and measuring the residual activity with a sodium iodide crystal system. The photoneutron cross section shows maxima at 11.7, 13.2, 15.2, 19.5, and 22.8 Mev, the last two being in the giant resonance region. The integrated cross section from threshold to the beginning of the giant resonance region is 1.8 Mev-mb, and this is compared with a recent theoretical prediction. During the course of the experiment, accurate measurements were made of the half-life of N13 and it was found to be 9.93 ± 0.05 minutes.

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Identification of the flax fibre modulus based on an impregnated quasi-unidirectional fibre bundle test and X-ray computed tomography

Composites Science and Technology ◽

10.1016/j.compscitech.2017.07.029 ◽

2017 ◽

Vol 151 ◽

pp. 124-130 ◽

Cited By ~ 9

Author(s):

Ilya Straumit ◽

Dirk Vandepitte ◽

Martine Wevers ◽

Stepan V. Lomov

Keyword(s):

Computed Tomography ◽

Fibre Bundle ◽

Flax Fibre ◽

X Ray ◽

X Ray Computed ◽

Unidirectional Fibre

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Magnetic Circular Dichroism in X-Ray Fluorescence

MRS Proceedings ◽

10.1557/proc-307-111 ◽

1993 ◽

Vol 307 ◽

Cited By ~ 2

Author(s):

L.-C. Duda ◽

C. F. Hague ◽

D. C. Mancini ◽

J.-M. Mariot ◽

C. Marliere ◽

...

Keyword(s):

Synchrotron Radiation ◽

Theoretical Prediction ◽

Spin Polarization ◽

Emission Band ◽

Fluorescence Spectra ◽

Magnetic Circular Dichroism ◽

High Flux ◽

Circularly Polarized ◽

X Ray ◽

Valence Electrons

ABSTRACTX-ray fluorescence spectra from magnetized iron excited by circularly polarized synchrotron radiation are reported. The Fe L2.3 emission band gives rise to a distinct dichroic signal in confirmation of a recent theoretical prediction. These preliminary experiments carried out with “white” and only partially circularly-polarized synchrotron radiation nevertheless reveal an asymmetry which reflects the spin polarization of the Fe 3d valence electrons. The usefulness of developing specialized high flux circularly-polarized sources is clearly established.

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Synthesis and X-ray structural characterization of the centred icosahedral gold cluster compound [Aul3(PMe2Ph)10Cl2](PF6)3; the realization of a theoretical prediction

Journal of the Chemical Society Chemical Communications ◽

10.1039/c39810000201 ◽

1981 ◽

pp. 201 ◽

Cited By ~ 245

Author(s):

Clive E. Briant ◽

Brian R. C. Theobald ◽

James W. White ◽

Linda K. Bell ◽

D. Michael P. Mingos ◽

...

Keyword(s):

Theoretical Prediction ◽

Structural Characterization ◽

Gold Cluster ◽

Cluster Compound ◽

X Ray

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Synthesis, X-ray Structure, Spectroscopic Characterization, and Theoretical Prediction of the Structure and Electronic Spectrum of Eu(btfa)3·bipy and an Assessment of the Effect of Fluorine as a β-Diketone Substituent on the Ligand−Metal Energy Transfer Process

Inorganic Chemistry ◽

10.1021/ic971602v ◽

1998 ◽

Vol 37 (14) ◽

pp. 3542-3547 ◽

Cited By ~ 87

Author(s):

Hélcio J. Batista ◽

Antônio V. M. de Andrade ◽

Ricardo L. Longo ◽

Alfredo M. Simas ◽

Gilberto F. de Sá ◽

...

Keyword(s):

Energy Transfer ◽

Theoretical Prediction ◽

Electronic Spectrum ◽

Transfer Process ◽

Energy Transfer Process ◽

Spectroscopic Characterization ◽

X Ray

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Space and Time Distribution of Hard X-Ray Emission in a Loop at the Beginning of a Flare

International Astronomical Union Colloquium ◽

10.1017/s0252921100025446 ◽

1994 ◽

Vol 144 ◽

pp. 275-277

Author(s):

M. Karlický ◽

J. C. Hénoux

Keyword(s):

Time Distribution ◽

Electron Bombardment ◽

Spatial Evolution ◽

Superthermal Electrons ◽

Flare Loop ◽

X Ray ◽

Superthermal Electron ◽

Flare Loops ◽

Chromospheric Evaporation ◽

Temporal And Spatial

AbstractUsing a new ID hybrid model of the electron bombardment in flare loops, we study not only the evolution of densities, plasma velocities and temperatures in the loop, but also the temporal and spatial evolution of hard X-ray emission. In the present paper a continuous bombardment by electrons isotropically accelerated at the top of flare loop with a power-law injection distribution function is considered. The computations include the effects of the return-current that reduces significantly the depth of the chromospheric layer which is evaporated. The present modelling is made with superthermal electron parameters corresponding to the classical resistivity regime for an input energy flux of superthermal electrons of 109erg cm−2s−1. It was found that due to the electron bombardment the two chromospheric evaporation waves are generated at both feet of the loop and they propagate up to the top, where they collide and cause temporary density and hard X-ray enhancements.

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Some Problems in Understanding the Solar Corona

International Astronomical Union Colloquium ◽

10.1017/s025292110002491x ◽

1994 ◽

Vol 144 ◽

pp. 1-9

Author(s):

A. H. Gabriel

Keyword(s):

Solar Corona ◽

Solar Atmosphere ◽

Theoretical Modelling ◽

Total System ◽

Major Advance ◽

X Ray ◽

Proper Perspective ◽

Space Observations

The development of the physics of the solar atmosphere during the last 50 years has been greatly influenced by the increasing capability of observations made from space. Access to images and spectra of the hotter plasma in the UV, XUV and X-ray regions provided a major advance over the few coronal forbidden lines seen in the visible and enabled the cooler chromospheric and photospheric plasma to be seen in its proper perspective, as part of a total system. In this way space observations have stimulated new and important advances, not only in space but also in ground-based observations and theoretical modelling, so that today we find a well-balanced harmony between the three techniques.

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