Neslihan Ekinci

Gamma-ray energy absorption and exposure buildup factor studies in some human tissues with endometriosis

Human tissues with endometriosis have been analyzed in terms of energy absorption (EABF) and exposure (EBF) buildup factors using the five-parameter geometric progression (G-P) fitting formula in the energy region 0.015-15 MeV up to a penetration depth of 40 mfp (mean free path). Chemical compositions of the tissue samples were determined using a wavelength dispersive X-ray fluorescence spectrometer (WDXRFS). Possible conclusions were drawn due to significant variations in EABF and EBF for the selected tissues when photon energy, penetration depth and chemical composition changed. Buildup factors so obtained may be of use when the method of choice for treatment of endometriosis is radiotherapy.

Measurement of atomic L shell Coster-Kronig yields (f12, f23 and f13) for some elements in the atomic number range 59⩽Z⩽90

Non-radiative transitions cause changes in the generation of the intensity of the L lines. In order to investigate the physical quantities relevant to the L lines affected by the non-radiative transitions, experimental measurements were carried out using a Si(Li) x-ray spectrometer. Atomic L shell Coster-Kronig yields (f12, f13 and f23) for some elements in the atomic number range 59≤Z≤90 were determined. These selected measured semi-empirical values were also fitted by least squares to polynomials in Z of the form ∑nanZn (except for f13) and compared with theoretical and with earlier fitted values.

Determination of calcium and iodine in gall bladder stone using energy dispersive X-ray fluorescence spectrometry

Abstract Energy dispersive X-ray fluorescence techniques were used to analyze gall bladder stones. Enrichment of Ca and I was observed in the gall bladder stone taken from a patient. The concentration of Ca has been determined with an annular 55 Fe radioactive source and the concentration of I with an annular 241 Am radioactive source using the standard addition method in 2π geometry. A Si(Li)-detector was used to measure Ca and I concentrations in the gall bladder stones.

Measurement of atomic L shell fluorescence (ω1, ω2, ω3) and Auger (a1, a2 and a3) yields for some elements in the atomic number range 59≤Z≤85

Abstract A comprehensive set of theoretical Coster–Kronig and fluorescence yields are presented for atomic numbers 18≤Z≤100. These quantities are based on ab initio relativistic calculations. Agreement with experimental values is fair for ω1 and generally good for ω2, ω3 (Z≥54) [1] . Therefore, atomic L shell fluorescence (ω1, ω2, ω3) and Auger yields (a1, a2 and a3) for some elements in the atomic number range 59≤Z≤85 were determined. These selected measured semi-empirical values were also fitted by least squares to polynomials in the Z of the form ∑nanZn and compared with theoretical and with earlier fitted values.

Chemical effects on Lα/Lβ X-ray intensity ratios of Ba, La and Ce

Chemical effects on the Lα/Lβ X-ray intensity ratio of Ba, La and Ce were investigated. The vacancies in the L shell were created by 59.5 keV γ-rays from an Am-241 radioactive source and the L X-rays were measured using a Si(Li) detector with resolution 160 eV at 5.9 keV. The experimental values are given with the theoretical values of the pure elements.

Determination of iodine and calcium concentrations in the bread improver using EDXRF

Abstract A study was made on the determination of elemental composition of the bread improver using energy-dispersive X-ray fluorescence. Enrichment of I and Ca was seen in the bread improver. Concentration of I with an annular 241 Am radioactive source and concentration of Ca with an annular 55 Fe radioactive source were determined by using standard addition method in 2 π geometry. A Si(Li) detector and a multichannel analyzer were used to measure I and Ca concentrations in the bread improver.

A study of the energy absorption and exposure buildup factors of some anti-inflammatory drugs.

Human radiation exposure is increasing due to radiation development in science and technology. The development of radioprotective agents is important for protecting patients from the side effects of radiotherapy and for protecting the public from unwanted irradiation. Radioprotective agents are used to reduce the damage caused by radiation in healthy tissues. There are several classes of radioprotective compounds that are under investigation. Analgesics and anti-inflammatory compounds are being considered for treating or preventing the effects of damage due to radiation exposure, or for increasing the chance of survival after exposure to a high dose of radiation. In this study, we investigated the radioprotective effects of some analgesic and anti-inflammatory compounds by evaluating buildup factors. The gamma ray energy absorption (EABF) and exposure buildup factors (EBF) were calculated to select compounds in a 0.015-15 MeV energy region up to a penetration depth of 40 mfp (mean free path). Variations of EABF and EBF with incident photon energy and penetration depth elements were also investigated. Significant variations in both EABF and EBF values were observed for several compounds at the moderate energy region. At energies below 0.15 MeV, EABF and EBF values increased with decreasing equivalent atomic number (Z(eq)) of the samples. In addition, EABF and EBF were the largest for ibuprofen, aspirin, paracetamol, naproxen and ketoprofen at 0.05 and 0.06 MeV, respectively, and the EABF value was 0.1 MeV for aceclofenac. From these results, we concluded that the buildup of photons is less for aceclofenac compared to other materials.

Determination of the Sample Thicknesses by Intensity Ratio Measurement by Energy Dispersive X-Ray Fluorescence Spectrometry

Abstract A procedure for the determination of the thickness of Au and Ag films and foils coated on a metallic Cu foil (substrate) is described. The procedure is based on the measurements of the fluorescence intensity ratios for two lines from the substrate element, excited by 59.5 keV photons emitted from a filtered Am-241 radioisotope source. The result of the procedure yielded between 0.039×10−5 and 4.3322×10−5 g/cm2 for Au and between 0.0394×10−5 and 5.8364×10−5 g/cm2 for Ag. These are tested by gravimetric measurements. The proposed procedure can also be employed to determine the density of the covering material or the incoming and outgoing angles of the radiation if the film thickness is known.

Determination of Ore Concentrates by Energy Dispersive X-Ray Fluorescence Spectrometry

Abstract EDXRF analysis has broad applications in the quantitative analysis of major and minor elements in geological, geochemical, and environmental studies, including the fields of sedimentology, stratigrapy, geochemistry, and mineral exploration. Evaluation of its potential for the analysis of major and minor elements in Bozalt and Dedemaksut ores were performed. Physical basis of used standard addition method, experimental set-up, the procedure of sample preparation and the results of analysis were presented. The correlation coefficients for each of elements analyzed (r greater than 0.986) were achieved.

The analysis of leiomyomata uteri and uterus using energy-dispersive X-ray fluorescence spectrometry

The X-ray fluorescence method was used to determine concentrations of the elements present in leiomyomata uteri and uterus. The physical basis of the analytical method used, experimental set-up, procedure of sample preparation, and the results are presented. The equipment used for this study was a Si(Li) detector, a multichannel analyzer, and 55Fe and 241Am radioisotope sources. The energy-dispersive X-ray fluorescence technique has been successfully used for the determination of elements present in leiomyomata uteri and uterus.