Energy-dispersive x-ray spectroscopy: Escape peaks of some biomaterials in the light-element region

1994 ◽  
Vol 52 ◽  
pp. 474-475
Author(s):  
Susan J. Okerstrom
Keyword(s):  
Noble Metals ◽  
Light Element ◽  
Energy Dispersive ◽  
Platinum Electrodes ◽  
High Corrosion Resistance ◽  
X Ray ◽  
Beryllium Window ◽  
Pacemaker Electrodes ◽  
High Concentrations ◽  
Electrical Conductors

The phenomena of escape peaks is well known, but caution must be exercised to avoid confusion in peak identification. A summary of our experiences with certain escape peaks may be useful to others.In biomedical devices, metal components are often used in pure elemental form or as alloys with high concentrations of a particular element. Noble metals such as gold, platinum and iridium are commonly used in pacemaker components. These metals are body compatible, have high corrosion resistance and are good electrical conductors. Pacemaker electrodes are commonly made of platinum, used alone or alloyed with about 10% iridium. These materials are routinely analyzed using the scanning electron microscope (SEM) with energy-dispersive x-ray spectroscopy (EDS).While analyzing platinum electrodes at 20 keV with the Beryllium window open, it was noted that an unexpected peak was seen in the spectrum near where carbon would be expected at 0.310 keV. The same peak was noted when the Be window was closed (figure 1). It was first thought to be a detector problem.

Simultaneous determination of trace elements in lavage fluids from human bronchial alveoli by energy-dispersive x-ray fluorescence. 3. Routine analysis.

1987 ◽  
Vol 33 (12) ◽  
pp. 2234-2239 ◽  
Author(s):  
E A Maier ◽  
A Dietemann-Molard ◽  
F Rastegar ◽  
R Heimburger ◽  
C Ruch ◽  
...  
Keyword(s):  
Trace Elements ◽  
Occupational Exposure ◽  
Bronchoalveolar Lavage ◽  
Normal Values ◽  
Energy Dispersive ◽  
Fluorescence Technique ◽  
X Ray ◽  
High Concentrations ◽  
Number Of Cells

Abstract We applied the energy-dispersive x-ray fluorescence technique to determination of trace elements in human bronchoalveolar lavage fluids. Our analysis of more than 200 samples allowed us to determine normal reference values, to be used in characterizing occupational exposure. These values are expressed both in nanograms per 1000 cells (of all kinds) and nanograms per 1000 macrophages to correlate lavage efficiency and dust content of the alveoli. The result expressed in milligrams per liter is not sufficient, because some healthy volunteers showed high concentrations of iron but normal values when expressed vs the number of cells. Some examples of abnormal compositions of broncho-alveolar lavages are reported and the fully automated spectrometer developed for clinical and biological investigations is described.

ENERGY DISPERSIVE X-RAY ANALYSIS OF FIELD PEAS WITH DIFFERENT COOKING QUALITY

1983 ◽  
Vol 63 (4) ◽  
pp. 1071-1074 ◽  
Author(s):  
J. CHONG ◽  
S. T. ALI-KHAN ◽  
B. B. CHUBEY ◽  
G. H. GUBBELS
Keyword(s):  
Statistical Analysis ◽  
Pisum Sativum ◽  
Cooking Quality ◽  
Energy Dispersive ◽  
Protein Bodies ◽  
X Ray ◽  
Pisum Sativum L ◽  
Field Peas ◽  
Freeze Dried ◽  
High Concentrations

An energy dispersive X-ray (EDX) analytical method was used to study the freeze-dried powder of seeds of field peas (Pisum sativum L.) with good and poor cooking quality. EDX analysis of the electron-dense particles in the freeze-dried powder revealed the presence of high concentrations of Mg, P, and K, suggesting that the particles were protein bodies. Seeds with different cooking quality were compared with respect to the ratios of these elements in the dense particles. Statistical analysis indicated a significant correlation between these ratios and cooking quality.Key words: Pisum sativum, protein bodies, elemental analysis

Effect of X-ray Tube Window Thickness on Detection Limits for Light Elements in XRF Analysis

1994 ◽  
Vol 38 ◽  
pp. 299-305
Author(s):  
Daniel J. Whalen ◽  
D. Clark Turner
Keyword(s):  
Light Element ◽  
Detection Limits ◽  
X Rays ◽  
Light Elements ◽  
Absorption Data ◽  
Element Analysis ◽  
X Ray ◽  
Data Compilation ◽  
Beryllium Window ◽  
X Ray Background

Abstract Widespread interest in light element analysis using XRF has stimulated the development of thin x-ray tube windows. Thinner windows enhance the soft x-ray output of the tube, which more efficiently excite the light elements in the sample. A computer program that calculates the effect of window thickness on light element sample fluorescence has been developed. The code uses an NIST algorithm to calculate the x-ray tube spectrum given various tube parameters such as beryllium window thickness, operating voyage, anode composition, and take-off angle. The interaction of the tube radiation with the sample matrix is modelled to provide the primary and secondary fluorescence from the sample. For x-rays in the energy region 30 - 1000 eV the mass attenuation coefficients were interpolated from the photo absorption data compilation of Henke, et al. The code also calculates the x-ray background due to coherent and incoherent scatter from the sample, as well as the contribution of such scatter to the sample fluorescence. Given the sample fluorescence and background the effect of tube window thickness on detection limits for light elements can be predicted.

scholarly journals Mineralogy of noble metals (Au, Ag, Pd, Pt) in Volkovskoe Cu-Fe-Ti-V deposit (Middle Urals, Russia)

LITOSFERA ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 653-659
Author(s):  
V. V. Murzin ◽  
G. A. Palyanova ◽  
E. V. Anikina ◽  
V. P. Moloshag
Keyword(s):  
Noble Metals ◽  
Native Gold ◽  
Middle Urals ◽  
Research Subject ◽  
Mineral Formation ◽  
X Ray ◽  
Two Generations ◽  
Magmatic Stage ◽  
Mineral Compositions ◽  
High Concentrations

Research subject. The mineral compositions of titanomagnetitic (apatite, titanomagnetite) and copper-titanomagnetitic (bornite, chalcopyrite, apatite, titanomagnetite) ores of the Volkovskoe Cu-Fe-Ti-V deposit (Middle Urals, Russia).Methods. The research was carried out using a Jeol JSM-6390LV scanning electron microscope and X-ray spectral microanalyzers JXA-5 (Jeol) at the Geoanalitik Collective Use Center of the IGG UB RAS. Results and conclusions.Native gold (with ≤ 0.3 wt % Pd, 0.2–0.4 wt % Cu; fneness 800–914 ‰), tellurides of Pd, Au and Ag (merenskyite, keithconnite, sylvanite, hessite) and Pt arsenide (sperrylite) were found in the copper-titanomagnetitic ores. For the frst time, two generations of native gold (fneness 1000 and 850–860 ‰) and palladium telluride (keithconnite Pd3-xTe) were detected in titanomagnetitic ores. The sequence of ore mineral formation and the features of their genesis were revealed. Native gold (fneness 1000‰) in the form of microinclusions in titanomagnetite was attributed to the magmatic stage. Noble metal minerals, intergrown with copper sulfdes (bornite, chalcopyrite, digenite) and associated with late hydroxyl-bearing minerals (amphibole, epidote, chlorite), are superimposed in relation to the magmatic minerals (pyroxene, plagioclase, hornblende, apatite, titanomagnetite, ilmenite, etc.) of these ores. Merenskyite, sperrylite, high fneness gold (800–914 ‰), as well as carrolite, cobaltite, copper-cobalt telluride and bismuth tellurium-selenide kawazulite Вi2Te2Se are syngenetic with copper sulfdes. The Au-Ag tellurides were deposited later than these minerals. It is shown that the high fugacity of tellurium, which binds Pd, Au, and Ag into tellurides, prevents the occurrence of native gold containing high concentrations of palladium and silver.

X-ray microanalysis of the mid-gut epithelium of the fruitfly Drosophila melanogaster

1975 ◽  
Vol 17 (3) ◽  
pp. 449-459
Author(s):  
R.L. Tapp
Keyword(s):  
Drosophila Melanogaster ◽  
Lower Limit ◽  
Atomic Number ◽  
Energy Dispersive ◽  
X Ray ◽  
Gut Epithelium ◽  
High Concentrations ◽  
Secondary Lysosomes

The cells in the mid-gut epithelium of Drosophila melanogaster which accumulate copper were examined by X-ray microanalysis. Both wavelength dispersive and energy dispersive analyses were used. The copper was located in granules o-3-1-o mum in diameter which were bounded by membranes and similar, morphologically, to secondary lysosomes. The copper was associated with high concentrations of sulphur but no other elements with an atomic number greater than 9 (the lower limit of the analysis equipment) were present in appreciable concentrations.

Do Ultra-Thin Polymer X-Ray Windows Leak Water Vapor?

1999 ◽  
Vol 5 (S2) ◽  
pp. 588-589
Author(s):  
A. Nielson ◽  
J. Thorne
Keyword(s):  
Water Vapor ◽  
Thin Layer ◽  
Liquid Nitrogen ◽  
Energy Dispersive Spectroscopy ◽  
Light Element ◽  
Energy Dispersive ◽  
Nitrogen Form ◽  
X Ray ◽  
The Past ◽  
Thin Polymer

Ultra-thin polymer x-ray windows have been developed for energy dispersive spectroscopy (EDS) that enable analysis of the elements lighter in mass than sodium while protecting the detector from light and gases. Windowless detectors produce the ultimate in detector sensitivity, however that sensitivity is lost when ice and other contaminants form on the detector. Polymer windows have had a problem with icing in the past, however modern ultra-thin polymer windows contain metalized layers to prevent the diffusion of water. Nevertheless, over the course of time it has been observed that some detectors with polymer windows that are kept continually cool with liquid nitrogen form a thin layer of ice that attenuates light element sensitivity. The source of this water has been hypothesized to be a gradual leak of water vapor through the polymer x-ray window. This hypothesis has been questioned on the basis that the windows were helium leak tight to 1 x 10−9 mbar L/sec and helium is a smaller molecule than water.

scholarly journals Enhancement of Low Energy / Light Element Energy Dispersive Analysis in the Scanning Electron Microscope Using a Non-Focusing X-Ray Optic

2009 ◽  
Vol 15 (S2) ◽  
pp. 218-219
Author(s):  
RE Edelmann ◽  
V Vasudevan ◽  
D Kohls ◽  
J Ullmer
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Light Element ◽  
Low Energy ◽  
Energy Dispersive ◽  
Energy Dispersive Analysis ◽  
X Ray ◽  
Dispersive Analysis ◽  
Scanning Electron

Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009

scholarly journals Petrogeochemical characteristics of chrome-bearing ultramafites in the Kurtushibinsky ophiolite belt (Western Sayan)

LITOSFERA ◽  
2019 ◽  
Vol 19 (5) ◽  
pp. 687-703
Author(s):  
A. I. Chernyshov ◽  
A. N. Yurichev ◽  
A. V. Kicheeva
Keyword(s):  
Noble Metals ◽  
Energy Dispersive Spectrometer ◽  
Energy Dispersive ◽  
Geochemical Data ◽  
Plastic Deformations ◽  
X Ray ◽  
Ophiolite Belt ◽  
Ore Minerals ◽  
Western Sayan ◽  
Composition Of Minerals

Research subject. The metamorphic ultramafites of the Kalninsky and Ergaksky massifs located in the northeastern part of Western Sayan (Russia) constitute the Kurtushibinsky ophiolite belt. These rocks are considered to be potentially interesting as bearing chromium and noble metals, which fact determines the relevance of this research.Materials and methods. Thin and polished sections of silicate and ore minerals from the ultramafic rocks under study were investigated using a polarizing microscope AxioScop, Carl Zeiss. The chemical composition of minerals was determined by the method of X-ray spectrum microanalysis using a scanning electron microscope Tescan Vega II LMU equipped with an energy-dispersive spectrometer INCA Energy 350 and a wave-dispersive spectrometer INCA Wave 700. The petrochemical composition of the rocks was studied by the methods of XRF analysis using an X-ray fluorescence energy-dispersive spectrometer Oxford ED-2000. A quantitative ICP-MS analysis was carried out using an Agilent 7500 spectrometer.Results. The massifs are found to be composed of dunites and harzburgites, which were formed during an uneven depletion of the mantle. As a result of depyroxenization, the ultramafites were enriched with chromospinelides. Subsequent intense plastic deformations contributed to their segregation into ore bodies. Regenerated olivinites predominate in the northern part of the Ergaksky massif. The microstructural features of ultramafites and the composition of minerals indicate them to have been subjected to inhomogeneous high-temperature plastic deformations, which occurred during their migration in the upper mantle and crust.Conclusions. The petrochemical studies have shown that the ultramafites of the Ergaksky massif are least depleted, frequently featuring clinopyroxene. The most depleted ultramafites of the Kalninsky massif are characterized by a more extensive distribution of dunites, the absence of clinopyroxene and lower contents of REE and rare elements in comparison with the ultramafites of the Ergaksky massif. The obtained geochemical data indicate a fluid-magmatic effect of boninite melts on depleted ultramafites, which apparently occurred under mantle conditions over the subduction zone and consequently led to their enrichment with incompatible LREE (La, Ce) and Sr, Zr and Hf, as well as to the formation of high-chromium chromitites. 

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