Determination of the composition of Ultra-thin Ni-Si films on Si: constrained modeling of electron probe microanalysis and x-ray reflectivity data

2008 ◽  
Vol 37 (6) ◽  
pp. 608-614 ◽  
Author(s):  
Tran M. Phung ◽  
Jacob M. Jensen ◽  
David C. Johnson ◽  
John J. Donovan ◽  
Brian G. McBurnett
1972 ◽  
Vol 16 ◽  
pp. 198-205
Author(s):  
J.D. Brown ◽  
L. Parobek

AbstractMeasurements of x-ray production as a function of depth in a sample (ϕ(ρz) curves) are fundamental to the determination of the quantitative equations for relating x-ray intensity to composition in electron probe microanalysis. These ϕ(ρz) curves have been measured for four different voltages and a number of different tracers in aluminum, copper, silver arid gold as matrix elements. From these ϕ(ρz) curves the absorption correction curves (f(x) curves) can be calculated. Such curves have been obtained and comparison is made with the absorption correction equations of Philibert. The effect of a tilted sample on the absorption correction is also discussed.


2021 ◽  
Vol 25 (2) ◽  
pp. 155-173
Author(s):  
A. G. Revenko ◽  

Current article considers the contribution of X-ray physicists from the city of Novosibirsk to the formation and development of the two X-ray spectral analysis directions: electron probe microanalysis and X-ray fluorescence analysis using the synchrotron radiation. The research on geological topics at the Institute of Geology and Geophysics of the Siberian Branch of the USSR Academy of Sciences using the MS-46 electron probe microanalyzer of the French company CAMECA (since 1967) served as the basis for the development of methods for the quantitative X-ray microanalysis of rock-forming minerals as the methods for quantitative determination of the contents of elements with low atomic numbers in the long-wavelength X-ray region were still in their infancy. With the development and the improvement of the method’s technical base (microprobes JXA-5A, JEOL, 1975; Kamebaks Micro, CAMECA, 1981; JXA-8100, JEOL, 2003; JXA-8230, JEOL, 2016; electronic computing), the software for controlling the operation of devices and converting the measured intensities of the analytical lines into the concentration of elements continued to changed and improve. The first results of elemental analysis, obtained using the synchrotron radiation to excite X-ray fluorescence at the VEPP-3 accelerating ring at the Institute of Nuclear Physics of the Siberian Branch of the USSR Academy of Sciences, were published in1977. Inthe following years, at the station of elemental SRXRF, samples of various nature were studied — biological (bio tissues of the heart, liver, lungs, hairs, bones, plants), geological, environmental objects (soils, sediments, aerosols, etc.), archaeological sites as well as new technological materials. The procedures for the determination of chemical elements in low-mass samples (milligrams) in unique samples of lunar soil samples, biopsy material of human myocardial tissues, etc. have been developed. The scanning device at the elemental SRXRF station made it possible to obtain the information for reconstructing the climate change for different periods of time – from 100 to 1000 years. A new non-destructive method of confocal X-ray microscopy for studying micro-objects and visualizing the distribution of chemical elements in extended objects on this station are currently being developed.


Author(s):  
A. LeFurgey ◽  
P. Ingram ◽  
L.J. Mandel

For quantitative determination of subcellular Ca distribution by electron probe x-ray microanalysis, decreasing (and/or eliminating) the K content of the cell maximizes the ability to accurately separate the overlapping K Kß and Ca Kα peaks in the x-ray spectra. For example, rubidium has been effectively substituted for potassium in smooth muscle cells, thus giving an improvement in calcium measurements. Ouabain, a cardiac glycoside widely used in experimental and clinical applications, inhibits Na-K ATPase at the cell membrane and thus alters the cytoplasmic ion (Na,K) content of target cells. In epithelial cells primarily involved in active transport, such as the proximal tubule of the rabbit kidney, ouabain rapidly (t1/2= 2 mins) causes a decrease2 in intracellular K, but does not change intracellular total or free Ca for up to 30 mins. In the present study we have taken advantage of this effect of ouabain to determine the mitochondrial and cytoplasmic Ca content in freeze-dried cryosections of kidney proximal tubule by electron probe x-ray microanalysis.


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