Standardless Quantification of Conductive Oxides In The Sem

1997 ◽  
Vol 3 (S2) ◽  
pp. 899-900
Author(s):  
J.M. Dijkstra ◽  
R.B Shen
Keyword(s):  
Light Element ◽  
Ease Of Use ◽  
Element Analysis ◽  
Measuring Device ◽  
Detector Window ◽  
Eds Analysis ◽  
Current Measuring ◽  
Type Detector ◽  
Achievable Accuracy ◽  
Standardless Analysis

In the last 10 years the development of new polymer type detector window materials has dramatically increased the opportunities for light element analysis with Energy Dispersive Spectrometers (EDS). With the introduction of light-element analysis the need also arises to accurately quantify X-ray spectra. Traditional quantification techniques, using a probe current measuring device and pure elemental standards, have been introduced into the field of EDS, but these techniques prevented much of the conveniences of the EDS techniques with respect to speed and ease of use. Many users are therefore willing to sacrifice part of the maximum achievable accuracy in return for a method that is more convenient: standardless analysis.With EDS analysis the widely published ZAF and φ(ρz) models can be used to convert relative intensities into weight percentages, but for standardless analysis the inaccuracy of the result is mainly caused by the reference intensities.

scholarly journals The use of pXRF for light element geochemical analysis: a review of hardware design limitations and an empirical investigation of air, vacuum, helium flush and detector window technologies

2020 ◽  
Vol 20 (3) ◽  
pp. 366-380 ◽  
Author(s):  
Cameron Adams ◽  
Christabel Brand ◽  
Michael Dentith ◽  
Marco Fiorentini ◽  
Stefano Caruso ◽  
...  
Keyword(s):  
Hardware Design ◽  
Light Element ◽  
Entrance Window ◽  
Element Analysis ◽  
X Ray ◽  
Detector Window ◽  
Scan Time ◽  
Mineralization Processes ◽  
Instrument Noise ◽  
Effectiveness Data

Light element data are required for robust and accurate lithogeochemical interpretations and are important components in the study of hydrothermal alteration and mineralization processes. In this contribution we review the latest available portable energy dispersive X-Ray Fluorescence (pXRF) technologies exclusively in the context of light element analysis, with focus on the acquisition of data for Na, Mg, Al and Si. We discuss pXRF hardware design limitations, quantify variables that attenuate X-ray energies through numerical modelling, including common pXRF configurations, and empirically investigate modern pXRF technologies used to mitigate X-ray attenuation and improve light element analysis.The void between the sample and detector is a key issue regarding the success of pXRF light element analysis. Dry-air (normal conditions), vacuum purge and helium flush systems are evaluated. Modelled data that use a nominal sample-detector void of 10 mm show that using helium in lieu of air improves X-ray transmission effectiveness from ≈2% to ≈99% for Na and ≈10% to ≈100% for Mg. Modelled detector window data show that using a graphene detector window in lieu of a traditional beryllium detector window improves X-ray transmission effectiveness for Na from ≈38% to ≈64% and ≈57% to ≈77% for Mg. Progressive X-ray transmission effectiveness equates to ≈63% Na and ≈76% Mg when using a helium-graphene pXRF configuration v. ≈1% for Na and ≈6% Mg when using a traditional in-air beryllium pXRF arrangement (i.e. without sample or X-ray entrance window media).Empirically determined improvements of the resolved signal are more modest than those of modelled X-ray transmission effectiveness data. Instrument noise, spectral overlaps and random counting errors are unavoidable and inherent with the limitations of modern detector technologies. However, the employment of helium with graphene detector window technology allows very precise data to be obtained at significantly shorter scan times (i.e. 20 s, instead of the traditional 60–180 s, i.e. 3–9 times faster): a scan time of 20 s can achieve a precision of ≈18% @ ≈0.4% Na and ≈8% @ ≈0.3% Mg for elemental interference-free samples. Precision will improve with increasing analyte concentration.

Computer programs for the calculation of x-ray intensities emitted by elements in multi-layer structures

1990 ◽  
Vol 48 (2) ◽  
pp. 216-217
Author(s):  
G.F. Bastin ◽  
H.J.M. Heijligers ◽  
J.M. Dijkstra
Keyword(s):  
Software Package ◽  
Light Element ◽  
Matrix Correction ◽  
Excellent Performance ◽  
Element Analysis ◽  
X Ray ◽  
Know How ◽  
Accurate Knowledge ◽  
Layer Structures ◽  
Bulk Matrix

For the calculation of X-ray intensities emitted by elements present in multi-layer systems it is vital to have an accurate knowledge of the x-ray ionization vs. mass-depth (ϕ(ρz)) curves as a function of accelerating voltage and atomic number of films and substrate. Once this knowledge is available the way is open to the analysis of thin films in which both the thicknesses as well as the compositions can usually be determined simultaneously.Our bulk matrix correction “PROZA” with its proven excellent performance for a wide variety of applications (e.g., ultra-light element analysis, extremes in accelerating voltage) has been used as the basis for the development of the software package discussed here. The PROZA program is based on our own modifications of the surface-centred Gaussian ϕ(ρz) model, originally introduced by Packwood and Brown. For its extension towards thin film applications it is required to know how the 4 Gaussian parameters α, β, γ and ϕ(o) for each element in each of the films are affected by the film thickness and the presence of other layers and the substrate.

The Influence of Specimen Thickness in Quantitative Electron Energy Loss Spectroscopy

1980 ◽  
Vol 38 ◽  
pp. 112-113
Author(s):  
Nestor J. Zaluzec
Keyword(s):  
Quantitative Analysis ◽  
Adverse Effects ◽  
Energy Loss ◽  
Electron Energy ◽  
Electron Energy Loss Spectroscopy ◽  
Materials Science ◽  
Light Element ◽  
Specimen Thickness ◽  
Element Analysis ◽  
Electron Energy Loss

The application of electron energy loss spectroscopy (EELS) to light element analysis is rapidly becoming an important aspect of the microcharacterization of solids in materials science, however relatively stringent requirements exist on the specimen thickness under which one can obtain EELS data due to the adverse effects of multiple inelastic scattering.1,2 This study was initiated to determine the limitations on quantitative analysis of EELS data due to specimen thickness.

Methodology for light element analysis of individual aerosol particles using thin-window EPMA

2000 ◽  
Vol 31 ◽  
pp. 765-766
Author(s):  
J. Osán ◽  
C.-U. Ro ◽  
I. Szalóki ◽  
A. Worobiec ◽  
J. De Hoog ◽  
...  
Keyword(s):  
Aerosol Particles ◽  
Light Element ◽  
Element Analysis

Half division two-dimensional method for simple sinusoidal quantities parameters accurate measurement

2021 ◽  
pp. 16-21
Author(s):  
Kirill Yu. Solomentsev ◽  
Vyacheslav I. Lachin ◽  
Aleksandr E. Pasenchuk
Keyword(s):  
Measuring Instruments ◽  
Measured Signal ◽  
Two Dimensional ◽  
Measuring Device ◽  
New Approach ◽  
Precision Measuring ◽  
Useful Signal ◽  
Midpoint Method ◽  
Order Of Magnitude ◽  
Current Measuring

Several variants of half division two-dimensional method are proposed, which is the basis of a fundamentally new approach for constructing measuring instruments for sinusoidal or periodic electrical quantities. These measuring instruments are used in the diagnosis of electric power facilities. The most general variant, called midpoint method, is considered. The proposed midpoint method allows you to measure much smaller than using widespread methods, alternating currents or voltages, especially when changing the amplitude of the measured signal in very wide ranges, by 1–2 orders of magnitude. It is shown that using the midpoint method it is possible to suppress sinusoidal or periodic interference in the measuring path, in particular, to measure small alternating current when sinusoidal or periodic interference is 1–2 orders of magnitude higher than the useful signal. Based on the results of comparative tests, it was found that the current measuring device implementing the midpoint method is an order of magnitude more sensitive than the currently used high-precision measuring instruments.

Light Element Analysis with TXRF

1992 ◽  
pp. 947-952 ◽  
Author(s):  
Christina Streli ◽  
Peter Wobrauschek ◽  
Hannes Aiginger
Keyword(s):  
Light Element ◽  
Element Analysis

Optimisation of light element analysis of individual particles using UTW-EPMA

2000 ◽  
Vol 31 ◽  
pp. 388-389
Author(s):  
J. De Hoog ◽  
J. Osán ◽  
A. Worobiec ◽  
C.-U. Ro ◽  
I. Szalóki ◽  
...  
Keyword(s):  
Light Element ◽  
Element Analysis ◽  
Individual Particles
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