X-ray excited optical fluorescence of trace rare earths in yttrium phosphate and yttrium vanadate hosts. Part per giga level determination of rare earth impurities in yttrium oxide

1973 ◽  
Vol 45 (3) ◽  
pp. 542-547 ◽  
Author(s):  
A P. D'Silva ◽  
V A. Fassel
Keyword(s):  
Rare Earth ◽  
Yttrium Oxide ◽  
Rare Earths ◽  
Yttrium Vanadate ◽  
X Ray ◽  
Optical Fluorescence ◽  
Rare Earth Impurities

Determination of trace rare earths by X-ray excited optical fluorescence

1968 ◽  
Vol 23 (11) ◽  
pp. 751-763 ◽  
Author(s):  
R.J. Jaworowski ◽  
J.F. Cosgrove ◽  
D.J. Bracco ◽  
R.M. Walters
Keyword(s):  
Rare Earths ◽  
X Ray ◽  
Optical Fluorescence

Determination of Trace Amounts of Rare-Earth Impurities in Yttrium Oxide

1968 ◽  
Vol 22 (2) ◽  
pp. 101-104 ◽  
Author(s):  
D. L. Nash
Keyword(s):  
Yttrium Oxide ◽  
Rare Earths ◽  
Signal To Noise Ratio ◽  
Graphite Powder ◽  
High Dispersion ◽  
Entire Height ◽  
Dc Arc ◽  
Rare Earth Impurities ◽  
Very High

This paper discusses investigations conducted to achieve optimum sensitivity for the determination of rare earths in yttrium oxide and describes a specific technique evolved for the above analysis. A dc arc burning in a controlled atmosphere of argon and oxygen is used together with a spectrograph of very high dispersion in order to provide optimum signal-to-noise ratio. Because the excitation efficiency is not uniform along the entire height of the arc column, only the most efficient portion is transmitted to the slit. Without any treatment or concentration of the sample other than dilution with graphite powder, the above method achieves sensitivities for the rare earths in yttrium oxide ranging from about 50 ppm for the least sensitive rare earths (Pr, Ce) to about 0.5 ppm for the most sensitive rare earths (Lu, Sc, Yb).

A Combined Dilution and Line-Overlap Coefficient Solution for the Determination of Rare Earths in Monazite Concentrates

1981 ◽  
Vol 25 ◽  
pp. 133-137
Author(s):  
T. K. Smith
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Atomic Number ◽  
Rare Earths ◽  
Microprobe Analysis ◽  
Matrix Effects ◽  
Emission Spectra ◽  
X Ray ◽  
Overlap Coefficient

The rare earth elements (REE) together give guite complex X-ray emission spectra with a considerable number of overlaps at analytical energies by lines of other REE with lower atomic numbers. Where the concentration of REE is high, as in lanthanide minerals, this Interference is more difficult to rectify. Smith and Gold resolved a similar problem with lower atomic number elements in energy dispersive microprobe analysis by establishing a series of overlap coefficients. They asserted that accurate corrections were necessary because of the relatively poor overall resolution of the instrument and that these should not be limited to the major coincidences. Some of the smaller values had probably been ignored because they were considered statistically Insignificant. The mathematical matrix of Smith and Gold covered 22 elements from fluorine to barium, with intensity coefficients (other than intraelement) quoted from 0.01% to 282.1% and with ZAF corrections necessary in cases of K to L conversion. The overlap coefficients were also adjusted for matrix effects.

Sign in / Sign up

Export Citation Format

Share Document