Energy-Dispersive X-Ray Emission Spectroscopy

1970 ◽  
Vol 24 (6) ◽  
pp. 557-566 ◽  
Author(s):  
R. S. Frankel ◽  
D. W. Aitken

A review is given of recent developments in energy-dispersive x-ray emission spectroscopy, with the aim of providing both an introductory and usefully practical look at this innovative field. The review begins with the first principles of x-ray production and observation, including a brief comparison of the performance capabilities of different types of detectors, but then specializes to a major extent in solid state x-ray spectrometers, which have led to the most significant new developments and applications. Evidence is presented which suggests that we are nearing an asymptotic limit in the attainment of ever better resolution with these types of systems. Applications that have been made possible by significant improvements in system resolution are discussed, but in the context of the need for a realistic appraisal of over-all system requirements. The great advantages offered by the marriage of silicon x-ray spectrometers to scanning electron microscopes and electron microprobe analyzers are reviewed and illustrated.

Author(s):  
Dale E. Newbury

Electron beam x-ray microanalysis with energy dispersive x-ray spectrometry (EDS), as performed in electron probe microanalyzers (EPMA)/scanning electron microscopes (SEM) for thick specimens and analytical electron microscopes (AEM) for thin sections, is a powerful technique with wide applicability in the physical and biological sciences and technology communities. The operation of an EDS x-ray microanalysis system has been automated to the point that many users now consider EDS to be a routine tool where the results reported by the automation system are always correct Unfortunately, there are numerous pitfalls awaiting the unwary analyst. All EDS users require a basic level of literacy in x-ray microanalysis to properly interpret spectra and develop a sensible analysis strategy for their problems. This “basic literacy” includes knowledge of the factors controlling the efficiency of production of characteristic and continuum x-rays, the characteristic energies and structure of x-ray families that provide the basis for qualitative analysis, the operational characteristics of energy dispersive x-ray spectrometers, including artifacts, and the systematic procedures for qualitative and quantitative analysis.


2014 ◽  
Vol 407 (11) ◽  
pp. 3045-3053 ◽  
Author(s):  
Vanessa Rackwitz ◽  
Michael Krumrey ◽  
Christian Laubis ◽  
Frank Scholze ◽  
Vasile-Dan Hodoroaba

2010 ◽  
Vol 97-101 ◽  
pp. 3879-3883 ◽  
Author(s):  
Zhi Bo Yang ◽  
Jiu Hua Xu ◽  
Ai Ju Liu

Brazing diamond grits onto steel substrate using a Ni-based filler alloy was carried out via laser beam in an argon atmosphere. The microstructure of the interfacial region among the Diamond grits and the filler layer were investigated by means of scanning electron microscopes (SEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS). Meanwhile, the formation mechanism of carbide layers was discussed. All the results indicated that the active element chromium in the Ni-based alloy concentrated preferentially to the surface of the grits to form a chromium-rich layer, and the hard joint between the alloy and the steel substrate is established through a cross-diffusion of iron and Ni-based alloy through parameters optimization.


Metals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 1026 ◽  
Author(s):  
Abbas Bahrami ◽  
Peyman Taheri

This paper investigates a failure in HP-Mod radiant tubes in a petrochemical plant. Tubes fail after 90,000 h of working at 950 °C. Observed failure is in the form of excessive bulging and longitudinal cracking in reformer tubes. Cracks are also largely branched. The microstructure of service-exposed tubes was evaluated using optical and scanning electron microscopes (SEM). Energy-dispersive X-ray spectroscopy (EDS) was used to analyze and characterize different phases in the microstructure. The results of this study showed that carbides are coarsened at both the inner and the outer surface due to the long exposure to a carburizing environment. Metallography examinations also revealed that there are many creep voids that are nucleated on carbide phases and scattered in between dendrites. Cracks appeared to form as a result of creep void coalescence. Failure is therefore attributed to creep due to a long exposure to a high temperature.


1999 ◽  
Vol 5 (S2) ◽  
pp. 310-311
Author(s):  
I.R. Barkshire ◽  
P. Karduck ◽  
W. Rehbach ◽  
S. Richter

Conventionally, x-ray microanalysis on scanning electron microscopes (SEM) with energy dispersive spectrometers (EDS) has been performed with relatively high primary energies (>10 kv). for most samples this results in reasonably good separation of the generated x-ray line series from different elements enabling unambiguous identification and therefore accurate qualitative analysis. Under these circumstances it is widely accepted that quantitative analysis of polished bulk samples is possible on a routine basis with relative errors around 1-5% and detection limits of the order of 0.1%.However, in order to address the analysis requirements of new advanced materials with sub-micron features, there is growing interest in performing x-ray microanalysis at low beam energies(<5kv). this is now a more realistic goal due to the routine availability of field emission sem's which can operate with much improved beam sizes at low beam energies with sufficient beam current to perform practical microanalysis, in conjunction with the improved low energy performance of current, commercially available EDS systems.


1999 ◽  
Vol 5 (S2) ◽  
pp. 604-605
Author(s):  
J.Höhne ◽  
M. Altmann ◽  
G. Angloher ◽  
M. Bühler ◽  
F.v. Feilitzsch ◽  
...  

AbstractCryogenic detectors with excellent energy resolution and low energy threshold far beyond the level of semiconducting detectors open a variety of new. applications in physics including search for Dark Matter in the universe [2], neutrino physics [3], and IR-, UV- and X-ray astrophysics [4, 9]. Interdisciplinary fields where cryogenic detectors have already shown promising results are the detection of biomolecules [5] and X-ray spectroscopy at synchrotron beam lines [6] and in scanning electron microscopes (SEMs) [7]. For both, astrophysical and analytical use, the development of high resolution microcalorimeters based on iridium/gold phase transition thermometers and aluminum tunnel junctions for use in a compact and universal detector system was initiated.Our cryogenic microcalorimeters consist of an absorber, a temperature sensor and a weak coupling to a heat sink. An X-ray photon interacts with the absorber and raises its temperature. The sensor measures the temperature increase and the system then, mediated by the coupling, relaxes back to its operating temperature.


1977 ◽  
Vol 86 (4) ◽  
pp. 525-540 ◽  
Author(s):  
David J. Lim ◽  
William H. Saunders

A total of 32 otosclerotic stapes is thin-sectioned without decalcification and examined using transmission and scanning electron microscopes, with a nondispersive x-ray analyzer attached to the latter. These otosclerotic stapes are classified as spongiotic, sclerotic, or preotosclerotic, according to their pathologic characteristics and state of mineralization. Either diffuse or patchy demineralization in the ground substance appears to be the initial stage of otosclerosis, and this area coincides with preotosclerotic lesions (also known as blue mantle) in light microscopy. Therefore, it is interpreted that demineralization precedes the destruction of ground substance in the preotosclerotic lesion. Bone mineral deposits in new otosclerotic bone appear to be related to the collagen fibrils that are embedded in the ground substance. No mineral deposit could be seen without the ground substance deposition; therefore, it is suggested that this ground substance is the single most important factor in the poor mineralization of the otosclerosis. The sclerotic lesions are well mineralized and show a typical pattern of hydroxyapatite by x-ray diffraction study. We could not confirm the notion that the sclerotic lesion is hypermineralized as compared to the normal stapes. The spongiotic lesions are poorly mineralized, with low calcium salt. Using the Ca/P ratio and x-ray diffraction pattern as criteria, it was determined that spongiotic lesions belong to unstable, immature bone.


2012 ◽  
Vol 109 (47) ◽  
pp. 19103-19107 ◽  
Author(s):  
R. Alonso-Mori ◽  
J. Kern ◽  
R. J. Gildea ◽  
D. Sokaras ◽  
T.-C. Weng ◽  
...  

2014 ◽  
Vol 955-959 ◽  
pp. 30-33
Author(s):  
Ling Liu ◽  
Xiao Jun Zhang ◽  
Jian Zhou Liu

A facile one-step solvothermal route was developed to synthesize NiO nanoflowers (200-300 nm in diameter) with the introduction of poly(vinyl-pyrrolidone)/stearic acid (PVP/SA) mixture. The product was characterized by X-ray powder diffraction (XRD), field-emission scanning electron microscopes (FESEM), Fourier transform infrared spectrometry (FT-IR), Thermal gravimetric analyze (TGA), and Brunauer-Emmett-Teller (BET). The mesoporous NiO nanoflowers showed an excellent adsorption capacity for organic pollutants (Congo red) from waste water (about 56 mg Congo red per g NiO).


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