Durdağı, Sevil; Güzel, Fatma

Emitted X-ray energies, line shapes, fluorescence yields, absorption probabilities and absorption edges of the elements are X-ray fundamental parameters that are of practical significance because they facilitate compositional analysis of complex materials. They are also a potent test of atomic theory. The chemical effects may cause changes in the energy of the X-ray lines and line shapes, such as the full width at half maximum and asymmetry index values depending on the chemical state of the substance. Although these effects vary for each element, the causes of these differences have been investigated. In this study, changes in chemical action values of lanthanide group compounds were investigated using a single crystal wavelength dispersive X-ray spectrometer equipped with a rhodium anode X-ray tube. The Ll and Lη X-ray emission lines are characterized by fitting of the Lorentz function. The chemical shift was investigated according to the chemical bond type, molecular structure, and oxidation number.

Yılmaz, Demet; Akkuş, Tuba; Kalecik, Sedanur

The albedo factors (number, energy, and dose) of samples with different thicknesses were measured at a scattering angle of 180°. Ten samples with mass thickness between 0.081 and 0.348 g/cm2 were prepared from praseodymium powder and twelve samples with the mass thicknesses from 0.068 to 0.620 g/cm2 were prepared from hafnium powder. The samples were irritated by 59.54 and 662 keV gamma rays emitted from Am241 and Cs137 radioactive sources, respectively. The scattered photons were counted by a high purity germanium detector with active area of 200 mm2. The albedo factors decreased with the atomic number and increased with the mass thickness.

Yilmaz, Demet; Dal, Mevşen Pirimoğlu; Akkuş, Tuba

The effect of the external mechanical noise on energy dispersive X-ray fluorescence (EDXRF) spectra has been investigated. A Nd2O3 sample was bombarded by the gamma-rays of 59.54 keV energy. The annular radioactive source (americium-241) with intensity equal to 1 Curie was used. The intensities of characteristic x-rays emitted from the Nd2O3 sample were measured using a high purity germanium detector. The mechanical noise applied to the experimental system had intensity values of 50 dB, 60 dB, 70 dB, 80 dB, 90 dB, and 100 dB. A sound level meter (Model 8928) was used to measure the external mechanical noise levels. The net area (P), background intensity (B), peak-to-background ratio (P/B), and full width at half-maximum (FWHM) of the characteristic peaks were determined in the energy dispersive X-ray fluorescence spectra obtained from Nd2O3 sample. It was observed that the background intensities of Kα and Kβ peaks of the sample increased with the increasing mechanical noise level. The peak-to-background ratios (P/B) and the peak resolution decreased with increasing mechanical noise level.

Gürol, A.; Ergen, E.; Karabulut, A.; Polat, R.; Altinkaynak, K.; Budak, G.

Human urinary stones, taken from recurrent urinary stone ailing patients, were investigated with an energy dispersive x-ray fluorescence (EDXRF) spectrometer. The concentrations of major elements in these stones, e.g., P, S, Cl, K, and Ca, were determined by using comparison-standard methods. This work is a contribution for doctors, to help minimize laboratory investigations and expenses, as well as the discomfort of patients, by speeding up the research of medical etiologic problems of patients with urinary stone disease.