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The results of an archaeometric investigation on painted pottery obtained from the archaeological excavations carried out in Kuriki (southeastern Anatolia) are presented. It was intended to reveal the production features of the painted pottery which were occasionally unearthed from the sites dated to the Late Iron Age and Hellenistic period. The samples were subjected to spectroscopic (X-ray diffraction), microscopic (optical microscopy, scanning electron microscope/energy dispersive X-ray spectroscopy) and thermal (thermogravimetric-differential thermal analysis) analysis techniques. It was deduced from the results that most of the ceramics were produced with calcareous clay batches. This assumption was supported by high amounts of CaO (detected through EDX), presence of calcite and occasionally the neo-formations (i.e. gehlenite, pyroxene) identified by XRD. The abundance of calcareous raw materials in the vicinity of the region therefore suggested a local production for the majority of the samples. Considering the mineral/phase contents of the potsherds and insufficient vitrification behavior in micro structure, the firing temperature of the samples was found to change between 700 °C and 900 °C, but mostly in the range of 800–900 °C. TG-DTA, used as a complementary technique, brought a convenient data in terms of elucidating the mineralogical content and the production properties. The same rock type (schist) determined through the petrographic analysis (OM) suggested that the raw materials used in production originated from the same or close sources. Finally, the results are compared with the outcome of the former archaeometric studies regarding the production features of various pottery types of Kuriki belonging to different time periods. [ABSTRACT FROM AUTHOR]

In recent years, the rapidly increasing search for compact, sustainable, and low-cost energy storage systems has led researchers to seek natural materials with high energy storage capability. Taking motivation from this point, our study has been focused on examining the physical, chemical, and dielectric properties of Kayseri Limestone (LS-K), Yahyalı stone (YS), and Edirne Limestone (LS-E) which have been collected from different regions of Turkey mines. The chemical content and structure of the stones have been determined by X-Ray Fluorescence analyzer and Fourier Transform Infrared spectrometry. The surface morphologies have also been visualized by Scanning Electron Microscope images. The frequency dependences of the components of complex permittivity, impedance, and ac conductivity have been examined at room temperature. It has been reported that LS-E has the greatest ε ′ value at 1–100 Hz interval. On the other hand, LS-K stands out as a low dielectric loss material with ε ″ values approximately 30 times and 24 times lower than YS and LS-E in the low-frequency range, respectively. Moreover, although the LS-K cannot have as high ε ′ values as the LS-E in the low-frequency region, it exhibits super-capacitive properties in a wide high-frequency interval of 47 kHz-40 MHz. The super-capacitive behavior of the LS-K has manifested itself with a phase angle of almost −90°. In particular, the LS-K that has ε ″ values of 0.02 and less in the frequency interval of 0.1 MHz–40 MHz becomes an inexpensive and natural promising candidate for high-frequency energy storage applications. • Geochemical and electric properties of two LS and Fe-shale were determined. • LS-K, YS, and LS-E were collected from different geographical regions of Turkey. • Impedance spectroscopy was employed to reveal the enery storage performance. • The LS collected from Edirne has remarkable high ε ′ values at low frequencies. • The LS belongs to Kayseri exhibited supercapacitive ability at high-frequency. [ABSTRACT FROM AUTHOR]

A new ceramic pigment material was obtained by the waste of processing chrome ore from the deposits of Pınarbaşı Village (Kayseri/Turkey) for industrial glaze application. The chemical analysis of waste powder was performed by X-ray fluorescence (XRF) analysis and the particle size analysis was carried out laser particle sizer. The waste powder was calcined at 900 °C and 1000 °C to investigate the color effect of synthesized pigments with different type of frits in industrial glazes. The factorial design of experiment was used for defining the main factors on color formation and parameters. The used factors were calcination temperature of waste powder, amount of waste powder, type of glaze and firing temperature. The spectrometer was employed for comparison of the coloring parameters (L*, a*, b*) of glazed tiles. The X-ray diffraction (XRD) and scanning electron microscope (SEM/EDX) analyses were performed in order to examine the phases and microstructures of glazed tiles. It was observed that the most effective factors were determined by factorial design of experiment as type of glaze and amount of waste powder for L* and b* parameters, type of glaze and firing temperature for a* parameter. Depending on the frit/glaze composition, the chromite processing waste provides a wide color range from brown to green tones in colored glazes for ceramic tiles. Factorial design experiment and microstructure analysis results reveal that chromite processing wastes is a strong alternative material as pigment to able to produce ceramic glazes and to contribute to waste elimination. [Display omitted] • This study includes the effects of chromite processing waste powder addition on glaze samples created with factorial design. • The amount of waste powder, frit type and firing temperature were important parameters on the optical properties. • The chromite processing waste provides a wide color range from brown to green tones in colored glazes for ceramic tiles. • From this study, it can be concluded that this waste powder can be used to produce economical pigment. • Statistical methodology can provide significant time savings by identifying appropriate factors and their levels. [ABSTRACT FROM AUTHOR]

Abstract: Oltu-stone is a unique black gemstone used commonly as an ornament in Turkey. The most distinctive characteristics of Oltu-stone are its strength and its reflective black appearance after polishing. It has been widely used since the 18th century as an important material for the production of quality prayer beads. This relatively hard stone is found in marine flysch and marl deposits as scattered chunks. Macroscopically, it more closely resembles obsidian than coal. Many scientists have researched the origins of this stone, but until recently, its genesis was not well understood. Its petrographical property is remarkable and quite interesting. In order to perform petrographical studies on Oltu-stone, ten samples were taken from two locations a few kilometers from the town of Oltu which is northeast of Erzurum city in eastern Turkey. Polished briquettes and thin sections were produced from the samples for petrographical examination under a coal microscope. SEM and EDS analyses were also conducted. Internal cellular structures can clearly be traced in fluorescent mode. The great strength of the stone has always incorrectly led to the conclusion that its genesis is unlike the genesis of coal. However, fluorescent light plainly revealed detailed cellular structures. With the aid of fluorescent light, suberinite textures and silicate filling of the cell cavities were clearly observed. [Copyright &y& Elsevier]

Dolomite is a carbonate mineral of calcium and magnesium having the chemical formula CaMg(CO 3) 2. It is a reservoir for significant petroleum reserves and mainly used as building and ceramic material. Thermoluminescence (TL) emission of this mineral has been examined in the literature, especially collected from Egypt, India, and Brazil. In this study, the aim is to investigate TL properties of dolomite mineral which has a wide reserve in Mersin/Turkey. Structural, morphological, and elemental analyzes were performed by X-ray Diffraction (XRD) Spectroscopy, Scanning Electron Microscope equipped with Energy Dispersive X-ray Spectrometer (SEM-EDS), and Inductively Coupled Plasma Mass Spectrometer (ICP/MS), respectively. TL measurements were carried out using a TL/OSL reader with a90Sr/90Y beta source. The natural TL (NTL) curve of the sample showed two peaks at around 255 and 345 °C by the wideband blue filter whereas an additional peak at 115 °C was observed under the beta irradiation. In addition, at high doses from 50 Gy, a shoulder at around 402 °C occurred. The optimum annealing temperature and duration of the sample were determined as 500 °C and 30 min. In order to remove the low-temperature peak, a preheating process at 200 °C with 23 s duration was applied before each TL readout. TL response to absorbed dose showed good linearity over the 0.1–1200 Gy dose range and the sample was observed to be reusable with only 1.7% change up to 10 cycles under a dose of 100 Gy. The kinetic parameters (activation energy E (eV), frequency factor s (s−1), kinetic order b) of the evident glow peaks were estimated using Peak Shape (PS), Various Heating Rate (VHR), Initial Rise (IR), and Computerized Glow Curve Deconvolution (CGCD) methods. The kinetic analysis indicated that the TL glow curve of the preheated sample consists of four individual peaks having activation energies of ∼1.56, 1.60, 1.78, and 1.73 eV, and these peaks obey second and general-order kinetics. • TL character of natural dolomite mineral originating in Turkey was investigated. • TL glow curve of the β-irradiated sample exhibited three peaks at 110, 255, and 345 °C and a shoulder at 402 °C at high doses. • The sample shows a good linear TL response in the 0.1–1200 Gy β-dose range. • The sample can be reused up to 10 sequential cycles with the deviation of 1.7%. • TL kinetic analyses revealed the decomposed peaks have second- and general-order kinetics. [ABSTRACT FROM AUTHOR]

Abstract: Chemical analyses performed on chrysoprase from Turkey have shown many trace elements as well as rare earth impurities. Quantitative chemical analyses of inclusions in minerals can improve our understanding of the chemistry of surface. The environmental scanning electron microscope (ESEM) with an attached X-ray energy dispersive system (EDS) is capable of producing rapid and accurate major element chemical analyses of individual inclusions in crystals larger than about 30μm in diameter. The samples were examined with lifetime-resolved and spatially-resolved cathodoluminescence (CL), and inductively coupled plasma-atomic emission spectrometry (ICP-AES). Spatially resolved CL results at room temperature were recorded for two different areas. Bulk area displays with low CL emission and pores contain iron phases such as chromite, hematite and anatase which cause the green color. For the raw data in the lifetime resolved CL spectrum, at least three broad emission bands were detected in a yellow band of the highest intensity at about 550nm, a weaker orange band at about 650nm, and a red band at 720nm. It is assumed that there are links between the CL emissions and the presence of some transition metal and REE elements, but it is obvious that all trace elements do not play a direct role. Micro-Raman measurements were performed on chrysoprase and these showed a characteristic intensive Raman band peaked at 464cm−1 which can be inferred to ν2 doubly symmetric bending mode of [SiO4/M] centers. Raman spectrum of all inclusions found in the material are also given and discussed in detail. [Copyright &y& Elsevier]

Abstract: In this study, material characteristics of historic oil paintings in a 19th century church in Ayvalık/Turkey were investigated to propose the treatments to be used in their conservation and protection. For this purpose, physical, chemical and mineralogical compositions and the microstructure of the paintings were determined by X-ray Diffraction, Scanning Electron Microscope, Thermo Gravimetric Analyzer, Differential Scanning Calorimeter, Infrared Spectroscopy and Laser Induced Breakdown Spectroscopy. Analysis results showed that the paintings were composed of very thin binding and white priming layers on which the pigments were applied. Binding layers were composed of polymerized vegetable oil with Zinc Oxide. Priming layers were composed of anglesite mineral in polymerized vegetable oil. Pigments used in paintings were mainly green earth, red chrome and iron oxide. [Copyright &y& Elsevier]

Beryllium oxide (BeO), which has a widely known single main TL peak over the main dosimetric region, is an important luminescent material widely used in personal, medical, and environmental dosimetry fields. The thermal and optically stimulated luminescence properties (TL and OSL) of the BeO dosimeter, supplied by a private company in Turkey (BeO R) that yields a double peak in the main dosimetric region (100–300 °C; heating rate = 2 °C/s) were studied. The corresponding properties were compared to the commercially prevalent Thermalox 995 BeO (BeO T). Multiple characterization techniques including x-ray diffraction analysis (XRD), energy dispersive x-ray spectroscopy (EDX), scanning electron microscope (SEM) image and electron spin resonance (ESR) were used to detect possible differences in TL and OSL signals. It was hypothesized that the calcination and or sintering process applied during the manufacturing process might lead to a double peak in the main dosimetric region of BeO R TL signals. Moreover, dosimetric properties of this dosimeter such as reproducibility, dose-response, minimum detectable dose (MDD), thermal quenching, bleaching, and thermal stability in combination with annealing properties were comprehensively investigated. An analysis of the results shows that BeO R has lower detection limits in TL than BeO T. In contrast, BeO T exhibited lower detection limits in the OSL signal than BeO R. Although both dosimeters have dissimilarities in several aspects, both are appropriate for dosimetric research on health physics applications. Therefore, selecting the appropriate BeO dosimeter could be an important factor to consider when assessing accurate doses in studies. With this outline in mind and by investigating using different characterization methods, the available luminescence knowledge base of BeO dosimeters was expanded. • Possible differences on TL and OSL signals were investigated for the two type of BeO dosimeters. • Dosimetric behaviours and kinetic parameters of BeO dosimeter were studied. • Multiple characterization techniques were applied to BeO dosimeters. [ABSTRACT FROM AUTHOR]