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Quartz, which is one of the most abundant minerals in nature, can be found in magmatic and metamorphic forms, as well as the usual components of granite and sedimentary formations. Quartz minerals, which are also known as the main component of quartzites, are also known as gangue minerals in many mineralizations. Quartz samples from two different sampling levels, namely the Kaletepe lower and the Kaletepe upper region, used in the study were prepared. Thermoluminescence (TL) glow curves of the samples exposed to radiation with a 90Sr/90Y β source were recorded with a TLD reader. While peaks were obtained at approximately 270 °C from the glow curves of the Kaletepe lower samples irradiated with β source, peaks were obtained at approximately 270 °C and 350 °C from the Kaletepe upper samples. When the annual average dose and age values of the lower and upper Kaletepe samples are examined, it can be said that it was formed in a time period of ~8000 years between two areas with a height difference of 130m. [ABSTRACT FROM AUTHOR]

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Undoped and different concentration Nd doped SrNbO powders with columbite structure were synthesized by molten salt process using a mixture of strontium nitrate and niobium (V) oxide and NaCl-KCl salt mixture as a flux under relatively low calcining temperature. X-ray diffraction analysis results indicated that SrNbO phases found to be orthorhombic columbite single phase for undoped, 0.5 and 3 mol% Nd doping concentrations. Phase composition of the powders was examined by SEM-EDS analyses. Radioluminescence properties of Nd doped samples from UV to near-IR spectral region were studied. The emissions increased with the doping concentration of up to 3 mol%, and then decreased due to concentration quenching effect. There is a sharp emission peak around 880 nm associated with F → I transition in the Nd ion between 300 and 1100 nm. The broad emission band intensity was observed from 400 to 650 nm where the peak intensities increased by increasing Nd doping concentration. All the measurements were taken under the room temperature. [ABSTRACT FROM AUTHOR]

Ceramic findings collected from Yeşilova Hoyuk located in Izmir were dated using the thermoluminescence dating technique. The area is of significant archaeological importance since it is the first prehistoric settlement in Izmir. Recent archeological observations suggest that human occupation of the region took place about 8500 years ago comparing to previously determined dates of 5000 years. Three samples collected from the same archaeological layer (Neolithic period) in Yeşilova Hoyuk were dated using the thermoluminescence method. Archaeological doses (AD) were obtained by single aliquot regenerative dose method (SAR) for thermoluminescence (TL) using coarse grain quartz minerals extracted from samples. Thick and thin AlO:C thermoluminescence dosimeters (TLD) were used to determine the annual dose rate. The archaeological doses were found to vary from 25.91±0.78 to 26.82±0.68 Gy, and the annual doses were found to be between 3.34±0.24 and 3.47±0.24 mGy/a. The ages obtained for the samples were determined to be 6000±830 BC, 5740±670 BC and 5460±740 years for samples ND1, ND2 and ND3, respectively, which supports the prediction of archeologist that the sampling layer dates from the Neolithic period. [ABSTRACT FROM AUTHOR]

Determination of the annual dose level of an area is one of the most important parameters in calculating the geological and archaeological age of the sample using luminescence techniques. Therefore, the concentrations of the natural radionuclides in soils and samples have to be determined since naturally occurring radioactivity provides a major contribution to the annual dose. In this study, the annual dose level of Salihli, Turkey, was determined with 2 different methods: an indirect method that involves the measurement of the concentrations of the naturally occurring radionuclides and a direct method in which thermoluminescence dosimeters (TLDs) are used. The concentrations of the natural radionuclides in soil samples were determined using HPGe γ-ray spectrometry. In the direct method, Al2O3:C thermoluminescence dosimeters were used. These dosimeters were chosen because of their high sensitivity and usability in dating studies. The results obtained from both methods were compared and discussed. [ABSTRACT FROM AUTHOR]