Quantitative Analysis of Scanning Transmission X-ray Microscopy Images of Gas-Filled PVA-Based Microballoons

Abstract The properties of core-shell nanoparticles, which are used for many catalytic processes as an alternative to platinum, depend on the size of both the particle and the shell. It is thus necessary to develop a quantitative method to determine the shell thickness. Pd–Pt core-shell particles were analyzed using scanning transmission electron microscopy (STEM) and energy-dispersive X-ray spectroscopy (EDX). Quantitative EDX line profiles acquired from the core-shell particle were compared to four core-shell models. The results indicate that the thickness of the Pt shell corresponds to two atomic layers. Meanwhile, high-angle annular dark-field STEM images from the same particle were analyzed and compared to simulated images. Again, this experiment demonstrates that the shell thickness was of two atomic layers. Our results indicate that, in small particles, it is possible to use EDX for a precise atomic-scale quantitative analysis.

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Why is my image noisy? A look into the terms contributing to a time-resolved X-ray microscopy image

Journal of Synchrotron Radiation ◽

10.1107/s1600577521004240 ◽

2021 ◽

Vol 28 (4) ◽

Author(s):

Simone Finizio ◽

Benjamin Watts ◽

Jörg Raabe

Keyword(s):

Photon Flux ◽

Dynamical Process ◽

Time Resolved ◽

X Ray ◽

Microscopy Image ◽

Experimental Parameters ◽

Scanning Transmission ◽

Imaging Conditions ◽

Microscopy Images

Through Monte Carlo simulations, we investigate how various experimental parameters can influence the quality of time-resolved scanning transmission X-ray microscopy images. In particular, the effect of the X-ray photon flux, of the thickness of the investigated samples, and of the frequency of the dynamical process under investigation on the resulting time-resolved image are investigated. The ideal sample and imaging conditions that allow for an optimal image quality are then identifed.

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Quantitative Analysis of Arsenic Doping Concentration in Silicon Using Scanning Transmission Electron Microscopy/Energy Dispersive X-ray Spectrometry

Science of Advanced Materials ◽

10.1166/sam.2018.2973 ◽

2018 ◽

Vol 10 (2) ◽

pp. 293-296

Author(s):

Sungho Lee ◽

Jonghyuk Kang ◽

Chilgee Lee ◽

Cheol-Woong Yang

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Quantitative Analysis ◽

Scanning Transmission Electron Microscopy ◽

Doping Concentration ◽

Energy Dispersive ◽

X Ray ◽

Scanning Transmission Electron ◽

Transmission Electron ◽

Scanning Transmission

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Quantification of Silica Uptake by Alveolar Macrophages - An Emperical Scanning Electron Microprobe Method

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100054297 ◽

1982 ◽

Vol 40 ◽

pp. 332-333

Author(s):

V. V. Damiano ◽

R. P. Daniele ◽

H. T. Tucker ◽

J. H. Dauber

Keyword(s):

Quantitative Analysis ◽

Alveolar Macrophages ◽

Bulk Sample ◽

Silica Particles ◽

Empirical Method ◽

Phagocytic Cells ◽

Calibration Standards ◽

X Ray ◽

Accurate Quantitative Analysis ◽

Scanning Electron

An important example of intracellular particles is encountered in silicosis where alveolar macrophages ingest inspired silica particles. The quantitation of the silica uptake by these cells may be a potentially useful method for monitoring silica exposure. Accurate quantitative analysis of ingested silica by phagocytic cells is difficult because the particles are frequently small, irregularly shaped and cannot be visualized within the cells. Semiquantitative methods which make use of particles of known size, shape and composition as calibration standards may be the most direct and simplest approach to undertake. The present paper describes an empirical method in which glass microspheres were used as a model to show how the ratio of the silicon Kα peak X-ray intensity from the microspheres to that of a bulk sample of the same composition correlated to the mass of the microsphere contained within the cell. Irregular shaped silica particles were also analyzed and a calibration curve was generated from these data.

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Lateral resolution of the electron microbeam analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109859 ◽

1978 ◽

Vol 36 (1) ◽

pp. 542-543

Author(s):

H.J. Dudek

Keyword(s):

Quantitative Analysis ◽

Depth Resolution ◽

Lateral Resolution ◽

Cylindrical Particle ◽

Correction Procedure ◽

X Ray ◽

Element Concentrations ◽

Microbeam Analysis ◽

The Matrix

The chemical inhomogenities in modern materials such as fibers, phases and inclusions, often have diameters in the region of one micrometer. Using electron microbeam analysis for the determination of the element concentrations one has to know the smallest possible diameter of such regions for a given accuracy of the quantitative analysis.In th is paper the correction procedure for the quantitative electron microbeam analysis is extended to a spacial problem to determine the smallest possible measurements of a cylindrical particle P of high D (depth resolution) and diameter L (lateral resolution) embeded in a matrix M and which has to be analysed quantitative with the accuracy q. The mathematical accounts lead to the following form of the characteristic x-ray intens ity of the element i of a particle P embeded in the matrix M in relation to the intensity of a standard S

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Microanalysis of precipitates in a ferritic steel

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100110234 ◽

1978 ◽

Vol 36 (1) ◽

pp. 618-619

Author(s):

J.M. Titchmarsh

Keyword(s):

Ferritic Steel ◽

Particle Identification ◽

Energy Dispersive ◽

Objective Lens ◽

Ferritic Steels ◽

Replica Technique ◽

X Ray ◽

Large Numbers ◽

Scanning Transmission ◽

Made In

The advances in recent years in the microanalytical capabilities of conventional TEM's fitted with probe forming lenses allow much more detailed investigations to be made of the microstructures of complex alloys, such as ferritic steels, than have been possible previously. In particular, the identification of individual precipitate particles with dimensions of a few tens of nanometers in alloys containing high densities of several chemically and crystallographically different precipitate types is feasible. The aim of the investigation described in this paper was to establish a method which allowed individual particle identification to be made in a few seconds so that large numbers of particles could be examined in a few hours.A Philips EM400 microscope, fitted with the scanning transmission (STEM) objective lens pole-pieces and an EDAX energy dispersive X-ray analyser, was used at 120 kV with a thermal W hairpin filament. The precipitates examined were extracted using a standard C replica technique from specimens of a 2¼Cr-lMo ferritic steel in a quenched and tempered condition.

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High-resolution x-ray imaging of small copper-rich precipitates in steels

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104704 ◽

1988 ◽

Vol 46 ◽

pp. 528-529

Author(s):

J. R. Michael ◽

K. A. Taylor

Keyword(s):

Electron Microscopy ◽

Thermomechanical Processing ◽

Atom Probe ◽

Ferrite Matrix ◽

Scanning Transmission Electron Microscope ◽

Probe Field ◽

X Ray ◽

Subsequent Transformation ◽

Transmission Electron ◽

Scanning Transmission

Although copper is considered an incidental or trace element in many commercial steels, some grades contain up to 1-2 wt.% Cu for precipitation strengthening. Previous electron microscopy and atom-probe/field-ion microscopy (AP/FIM) studies indicate that the precipitation of copper from ferrite proceeds with the formation of Cu-rich bcc zones and the subsequent transformation of these zones to fcc copper particles. However, the similarity between the atomic scattering amplitudes for iron and copper and the small misfit between between Cu-rich particles and the ferrite matrix preclude the detection of small (<5 nm) Cu-rich particles by conventional transmission electron microscopy; such particles have been imaged directly only by FIM. Here results are presented whereby the Cu Kα x-ray signal was used in a dedicated scanning transmission electron microscope (STEM) to image small Cu-rich particles in a steel. The capability to detect these small particles is expected to be helpful in understanding the behavior of copper in steels during thermomechanical processing and heat treatment.

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Energy Dispersive X-Ray Measurements of thin Metal Foils

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100092098 ◽

1976 ◽

Vol 34 ◽

pp. 426-427

Author(s):

J. Bentley ◽

E. A. Kenik

Keyword(s):

Materials Science ◽

Energy Dispersive Spectrometer ◽

Thin Foil ◽

Thin Metal ◽

Energy Dispersive ◽

Thin Specimen ◽

X Ray ◽

Metal Foils ◽

Small Probe ◽

Scanning Transmission

Instruments combining a 100 kV transmission electron microscope (TEM) with scanning transmission (STEM), secondary electron (SEM) and x-ray energy dispersive spectrometer (EDS) attachments to give analytical capabilities are becoming increasingly available and useful. Some typical applications in the field of materials science which make use of the small probe size and thin specimen geometry are the chemical analysis of small precipitates contained within a thin foil and the measurement of chemical concentration profiles near microstructural features such as grain boundaries, point defect clusters, dislocations, or precipitates. Quantitative x-ray analysis of bulk samples using EDS on a conventional SEM is reasonably well established, but much less work has been performed on thin metal foils using the higher accelerating voltages available in TEM based instruments.

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