Ö. Söğüt

Investigation by XRF and XRD of Zn and Fe in Fex Zn1−x thin films

FexZn1?x alloys were electrochemically deposited on aluminum substrates from a sulfate bath. The K?/K? x-ray intensity ratios of Zn and Fe in FexZn1?x thin films have been experimentally studied. The energy dispersive x-ray fluorescence (EDXRF) technique was used to measure K x-ray photons. Samples were excited by using 59.5?keV photons emitted by a 50 mCi 241Am radioactive source. The emitted K x-rays were detected by an Ultra-LEGe detector having a resolution of 150?eV at 5.9?keV. In addition, the effect of bath composition on the phase structure was investigated by x-ray diffraction (XRD) analysis. The composition of the thin films was analyzed by atomic absorption spectrometry analysis. Iron content was shown to strongly affect the structure of Zn?Fe alloys. It was found that the K-shell x-ray intensity ratio changed in FexZn1?x thin films for different values of x. The reason for this change may be that the electronegativity of iron is higher than that of zinc and that electron transfer from zinc to the outermost orbital of iron occurs. In conclusion, in FexZn1?x thin films, intensity ratio increases with increasing concentration of Zn but decreases with increasing concentration of Fe.

Measurement of gross alpha and gross beta activity concentrations in human tooth

The gross alpha and gross beta activity concentrations were measured in human tooth taken from 3 to 6 age-groups to 40 and over ones. Accumulated teeth samples are investigated in two groups as under and above 18 years. The gross alpha and beta radioactivity of human tooth samples was measured by using a gas-flow proportional counter (PIC-MPC 9604-alpha/beta counter). In tooth samples, for female age-groups, the obtained results show that the mean gross alpha and gross beta activity concentrations varied between 0.534-0.203 and 0.010-0.453 Bq g(-1) and the same concentrations for male age-groups varied between 0.009-1.168 and 0.071-0.204 Bq g(-1), respectively.

Measurement of Atomic L‐Subshell Coster‐Kronig Transition ( f 12) for Some Elements in the Atomic Range 52 ≤ Z ≤ 92

Abstract Coster‐Kronig transitions are a special class of radiationless transitions in which an atomic inner‐shell vacancy is filled by an electron from a higher subshell of the same principal shell (same quantum number, n). In order to investigate the physical quantities relevant to the L lines affected by the nonradiative transitions, experimental measurements were carried out using a Si(Li) x‐ray spectrometer. Atomic L shell Coster‐Kronig yields, f 12, for some elements in the atomic number 52 ≤ Z ≤ 92, were determined. The results in the present paper are found to be in good agreement with the theoretical values.

Measurement of the Kα to Lα and Kβ to Lβ intensity ratios of seven elements in the atomic number range 52≤Z≤62 using photoionization at 59.5 keV1

The Kα to Lα and Kβ to Lβ intensity ratios of seven elements have been measured following photoionization at 59.5 keV by using a Si (Li) detector (FWHM=155 eV at 5.96 keV). The intensity ratios were determined by measuring K and L x-rays emitted from a standard target of a given element. The theoretical values of the Kα to Lα and Kβ to Lβ intensity ratios were calculated using theoretically tabulated values of shell/subshell photoionization cross sections, fluorescence yields, Coster-Kronig transition probabilities, and radiative decay rates for ηKLi≠ and ηKLi=0. The measured values are in good agreement with theoretical results.