Practical Methods of Solving Absorption and Enhancement Problems in X-Ray Emission Spectrography
A description of the manner in which absorption and enhancement effects produce nonlinear relationships between intensity and concentration in X-ray fluorescence spectrography is given. Under certain circumstances enhancement may pose an asset in providing a means of increasing the detectability of an element in low or trace concentrations. Since absorption and enhancement are fundamental properties of matter, the practical approach in X-ray spectrographic analysis is to employ methods or techniques which surmount or circumvent their effects. Those used by various workers to accomplish this may be classified into three categories: (1) minimize or reduce these effects to negligible levels by attenuation or by sample dilution; (2) compensate for them by comparison or by internal standardization; (3) apply mathematical corrections to the observed measurements based either on empirical knowledge of the magnitude of these effects or on theoretical considerations. A discussion of examples from the methods of various workers which illustrate these general approaches is given.
KeywordsAtomic Number Absorption Edge Critical Depth Mass Absorption Coefficient Infinite Depth
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