X-Ray Fluorescence Analysis of Tungsten-Molybdenum Metals and Electrolytes

1960 ◽  
Vol 4 ◽  
pp. 474-487
Author(s):  
K. R. Stever ◽  
J. L. Johnson ◽  
H. H. Heady

AbstractAn X-ray fluorescence method is presented for the analysis of tungsten-molybdenum solutions. Tungsten and molybdenum metal powders, produced by a fused-salt electrolysis procedure, are dissolved and analyzed for tungsten and molybdenum by using the W La1, Pt La1 intensity ratios. The platinum spectral line from the X-ray tube target serves as a self-internal standard. The sensitivity limit is about 0,05% and in the concentration range of 0.5 to 100%, the accuracy of analysis is within about 2% standard deviation. The technique is also applied to the analysis of tungsten and molybdenum in fused salts and to the determination of several other Impurity elements in these metals.A double detector modification for the General Electric X-ray unit is described. The detector consists of a double-window flow proportional counter tube backed up by a sealed krypton-filled counter tube. This allows counting of either soft or hard radiation at maximum efficiencies without the necessity of changing counter tubes. Advantages in specific applications are discussed.

2020 ◽  
Vol 86 (10) ◽  
pp. 5-9
Author(s):  
D. G. Filatova ◽  
A. A. Arkhipenko ◽  
M. A. Statkus ◽  
V. V. Es’kina ◽  
V. B. Baranovskaya ◽  
...  

An approach to sorptive separation of Se (IV) from solutions on a novel S,N-containing sorbent with subsequent determination of the analyte in the sorbent phase by micro-x-ray fluorescence method is presented. The sorbent copolymethylenesulfide-N-alkyl-methylenamine (CMA) was synthesized using «snake in the cage» procedure and proven to be stable in acid solutions. Conditions for quantitative extraction of Se (IV) were determined: sorption in 5 M HCl or 0.05 M HNO3 solutions when heated to 60°C, phase contact time being 1 h. The residual selenium content in the solution was determined by inductively coupled plasma mass spectrometry (ICP-MS) using 82Se isotope. The absence of selenium losses is proved and the mechanism of sorption interaction under specified conditions is proposed. The method of micro-x-ray fluorescence analysis (micro-RFA) with mapping revealed a uniform distribution of selenium on the sorbent surface. The possibility of determining selenium in the sorbent phase by micro-RFA is shown. When comparing the obtained results with the results of calculations by the method of fundamental parameters, it is shown the necessity of using standard samples of sorbates to obtain correct results of RFA determination of selenium in the sorbent phase.


2010 ◽  
Vol 44 (1) ◽  
pp. 24-27 ◽  
Author(s):  
G. A. Bordovsky ◽  
A. V. Marchenko ◽  
P. P. Seregin ◽  
N. N. Smirnova ◽  
E. I. Terukov

1972 ◽  
Vol 9 (1) ◽  
pp. 36-42 ◽  
Author(s):  
Calvert C. Bristol

X-ray powder diffraction methods, successful in quantitative determination of silicate minerals in fine-grained rocks, have been applied to the determination of calcite, dolomite, and magnesite in greenschist facies meta-volcanic rocks. Internal standard graphs employing two standards (NaCl and Mo) have been determined.Carbonate mineral modes (calcite and dolomite) for 6 greenschist facies meta-volcanic rocks obtained by the X-ray powder method have been compared to normative carbonate mineral contents calculated for the same rocks. This comparison showed a maximum variation of 7.7 wt.% between the X-ray modes and the normative carbonate mineral contents of the rocks. Maximum standard deviation for the X-ray modes of these rocks was equivalent to 4.4 wt.%.


2015 ◽  
Vol 69 (5) ◽  
Author(s):  
Albena K. Detcheva ◽  
Svilen E. Mitsiev ◽  
Paunka S. Vassileva ◽  
Juri H. Jordanov ◽  
Metody G. Karadjov ◽  
...  

AbstractThe contents of Cl, Ca, K, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Rb, Sr, Ba and Pb in raw coal fly ash from five Bulgarian power plants were determined by total reflection X-ray fluorescence (TXRF), using gallium as the internal standard. The samples were analysed as in slurry form in Triton


1993 ◽  
Vol 37 ◽  
pp. 697-709 ◽  
Author(s):  
Krassimir N. Stoev ◽  
Joseph F. Dlouhy

Nowadays x-ray fluorescence analysis is one of the major techniques for determination of trace elements. Vacuum operated Si (Li) .energy-dispersive x-ray spectrometers can analyze simultaneously up to 50 elements from Na (Z=11) to U (Z = 92) . Proper interpretation of the accumulated spectra requires correct solution of x-ray line overlap problems. In many cases knowledge of x-ray intensity ratios can make the procedure for resolving the overlapped peaks more reliable and reproducible. Measurements of radiative transition rates can also provide fundamental tests of theoretical atomic structure calculations. There are many other useful applications of x-ray emission rates in theoretical and experimental physics. On the other hand, there are differences in the published data, which suggests that x-ray intensity ratios are still not known with the necessary accuracy, and new measurements are useful and necessary.


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