ANALYTICA CHIMICA ACTA, cilt.515, sa.2, ss.349-352, 2004 (SCI-Expanded)
To investigate the validity of the mixture rule which is used to compute the mass attenuation coefficients in compounds, the total mass attenuation coefficients for Cu, Cr elements and Cu2O, CuC2O4, CuCl2.2H(2)O, Cu(C2H3O2)(2).H2O, Cr2O3, Cr(NO3)(3), Cr-2(SO4)(3).H2O, Cr-3(CH3CO7)(OH)(2) compounds were measured at photon energies between 4.508 and 13.375 keV by using the secondary excitation method. Ti, Mn, Fe, Ni, Zn, Ge, As, Rb elements were used as secondary exciters. 59.5 keV gamma rays emitted from an Am-241 annular source were used to excite the secondary exciters and Kalpha (K-L-3, L-2) rays emitted from the secondary exciter were counted by a Si(Li) detector with a resolution of 160 eV at 5.9 keV. Our measurements indicate that the mixture rule is not a suitable method for the computation of mass attenuation coefficients of compounds especially at an energy that is near the absorption edge. Obtained values were compared with theoretical values. (C) 2004 Elsevier B.V. All rights reserved.