Abstract

Rose and Cuttita found a satisfactory solution by x-ray emission spectrography to the difficult problem of determining traces of bromide in saline waters by spiking the aliquots sample with bromide prior to measuring the intensity (counts per second) of Br <i>K</i>α on pellets of cellulose powder containing the spiked, dried sample. For such samples, the determination of background encounters two difficulties. Since bromide is present, the background cannot be counted directly at the wavelength of the analytical line, Br <i>K</i>α. Because pronounced and unknown absorption effects by the matrix modify the intensity of the analytical line, and of the background, determining the background on suitable blanks is cumbersome. Both difficulties were resolved graphically by the "slope-ratio method" devised by the investigators. The objectives here are to resolve these difficulties in a different way, and to delineate the physical basis of the background problem.

Statistics of the slope-method estimator

Francesc Rocadenbosch, Adolfo Comerón, and Lorena Albiol
Appl. Opt. 39(33) 6049-6057 (2000)

The Rose model, revisited

Arthur E. Burgess
J. Opt. Soc. Am. A 16(3) 633-646 (1999)

Slope method for determining extinction coefficients*

U. S. Whang, R. N. Hamm, E. T. Arakawa, and M. W. Williams
J. Opt. Soc. Am. 63(3) 305-308 (1973)

Inversion of lidar signals with the slope method

Gerard J. Kunz and Gerrit de Leeuw
Appl. Opt. 32(18) 3249-3256 (1993)

Application of statistical methods to the determination of slope in lidar data

David N. Whiteman
Appl. Opt. 38(15) 3360-3369 (1999)