Modified Micro Sample Support for X-Ray Emission Spectrography

1974 ◽  
pp. 331-332
Author(s):  
David A. Nickey ◽  
James O. Rice
Keyword(s):  
X Ray ◽  
Sample Support

Energy Dispersive X-ray Fluorescence Analysis Using Synchroton Radiation

1984 ◽  
Vol 28 ◽  
pp. 61-68 ◽  
Author(s):  
Atsuo Iida ◽  
Yohichi Gohshi ◽  
Tadashi Matsushita
Keyword(s):  
Fluorescence Analysis ◽  
Total Reflection ◽  
Energy Dispersive ◽  
High Signal ◽  
X Rays ◽  
X Ray ◽  
Background Ratio ◽  
Fluorescence Measurements ◽  
Sample Support ◽  
The Continuum

AbstractTrace element analyses by energy dispersive X-ray fluorescence measurements were made using synchrotron radiation from a dedicated electron storage ring at the Photon Factory in Japan. The continuum or the monochromatic beam was used for excitation. A crystal monochromator or two types of mirror systems were used for monochromatic excitation. A high signal to background ratio was attained with the crystal monochromator, while the highest absolute detectability was achieved with the mirror system. The minimum detection limita obtained from thin samples are of the order of 0.1 ppm or less than 0.1 pg. Furthermore the signal to background ratio was significantly improved by using an X-ray mirror as a sample support in which, external total reflection of exciting X-rays occured.

X-Ray Diffractometry of Low-Mass Samples

1987 ◽  
Vol 2 (2) ◽  
pp. 78-81 ◽  
Author(s):  
L. S. Zevin ◽  
I. M. Zevin
Keyword(s):  
Cross Section ◽  
Limit Of Detection ◽  
Bulk Sample ◽  
Primary Beam ◽  
Minimum Volume ◽  
Spreading Area ◽  
X Ray ◽  
Intensity Measurements ◽  
Low Mass ◽  
Sample Support

AbstractThe intensity diffracted by a low-mass sample with negligible absorption may be expressed as It = I∞ (B/2μ*)/G, where I∞ = intensity diffracted by a bulk sample, B = cross section of the primary beam, μ* = mass absorption coefficient, and G = mass of the sample. Measurable intensity may be obtained from samples with less than 1 μg mass. In order to improve the limit of detection, the primary beam should be collimated so as to irradiate the sample and only a minimum volume of the sample support. The optimum spreading area of a low-mass sample is S sinθ≅10μ*. Comminution of low-mass samples to 1 — 2μm particles is adequate for reasonable intensity measurements.

On the Relation between Filament Chirality, Rotation Direction, and Morphology

2020 ◽  
Author(s):  
Zhenjun Zhou ◽  
Rui Liu ◽  
Xing Cheng ◽  
Chaowei Jiang ◽  
Yuming Wang ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Coronal Mass Ejections ◽  
Geomagnetic Storms ◽  
Small Sample ◽  
New Method ◽  
Magnetic Orientation ◽  
X Ray ◽  
Rotation Direction ◽  
Sample Support ◽  
The Magnetic Field

<p>Coronal mass ejections (CMEs) with enhanced south-component of the magnetic field are susceptible to producing geomagnetic storms. Filament chirality, rotation direction, and morphology are responsible for CMEs’ magnetic orientation and they are manifestations of magnetic helicity. However, different models predict different relations among them. In this paper, taking advantage of stereoscopic observations and a new method of determining the chirality of erupting filaments, we analyze 12 filaments that present a clear rotation during the eruption. The results based on the small sample support the argument that the filaments with for sinistral (dextral) chirality, they rotate clockwise (counterclock-wise), indicating the transformation of twist into writhe. Moreover, we also inspect soft X-ray and EUV hot temperature images and find that, the associated sigmoids are consistent with filaments prior to the eruption morphologically. However, once starting to rise up, the erupting filaments reverse their shapes from forward S-shaped to inversed S-shaped and vice versa.</p>

scholarly journals Portable grazing exit X-ray fluorescence system using a low-power X-ray tube

2019 ◽  
Vol 7 (2A) ◽  
Author(s):  
Ramon Silva Dos Santos ◽  
Davi Ferreira De Oliveira ◽  
Joaquim Teixeira De Assis ◽  
Marcelino José Dos Anjos
Keyword(s):  
Low Power ◽  
Low Cost ◽  
Trace Elemental Analysis ◽  
X Ray ◽  
First Results ◽  
Trace Elemental ◽  
Portable System ◽  
Sample Support ◽  
Relative Errors ◽  
Certified Values

In this work was developed a portable system of grazing exit X-ray fluorescence (geometric 90° - 0°) that can be applied in several areas science and technology. GE-XRF portable system is formed by a mini X-ray tube of low power (anode of Au) and a SiPIN detector. The reflectors used as sample support (sampler carrier) were quartz discs. The grazing exit angle was experimentally determined by measuring a cooper solution (10 μg.g-1). The accuracy of the system was checked using multielement reference solution as standard reference material. The relative errors between measured and certified values are in the range of 4 to 19%. The first results showed a background was drastically reduced at grazing exit angles, enabling trace elemental analysis. The system of GE-XRF proved to be quite stable and reproducible. This paper shows that it is possible to produce a portable system of grazing exit X-ray fluorescence compact, efficient, low-cost and easy-to-handle instrumentation using a low power X-ray tube and a SiPIN compact detector.

Modified Micro Sample Support for X-Ray Emission Spectrography

1971 ◽  
Vol 25 (3) ◽  
pp. 383-383
Author(s):  
David A. Nickey ◽  
James O. Rice
Keyword(s):  
X Ray ◽  
Sample Support

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

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.

Some Problems in Understanding the Solar Corona

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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