Spectroscopic investigation of two Serbian icons painted on canvas

A multianalytical study of two Serbian icons, The Virgin and Child and St. Petka, painted on canvas by unknown authors was performed in order to identify the materials used as pigments, binders and the ground layer. The investigated icons belong to the Museum of the Serbian Orthodox Church in Belgrade. Samples, collected from different parts of the icons, were analysed by: optical microscopy (OM), energy dispersive X-Ray fluorescence (EDXRF), Fourier transform infrared (FTIR) and micro-Raman spectroscopy. The obtained results revealed the presence of the following pigments: Prussian Blue, ultramarine, Green Earth, iron oxides, Lead White and Zinc White. Linseed oil was used as the binder. The materials used for the ground layers were gypsum, calcite, baryte and Lead White. The gilded surface of the icon The Virgin and Child was made of gold. The gilded surface on the frame of this icon was made of imitation of gold, i.e., Schlagmetal, since EDXRF spectroscopy showed the presence of copper and zinc, while gold was not detected. Based on the style and the consideration of an art historian, as well as on the obtained results for the corresponding pigments and binder, both icons were most probably made at the end of 19th or the beginning of the 20th century

Physicochemical characterisation of pottery from the Vinca culture, Serbia, regarding the firing temperature and decoration techniques

A study of decorated Neolithic pottery samples from the excavation site Plocnik, Serbia, was performed using X-ray powder diffraction (XRPD), Fourier transform infrared (FTIR) and X-ray fluorescence (XRF) spectroscopy. The investigated samples belong to the era of the Vinca culture that existed in the central Balkan region from the mid VI until the first half of the V millennium BCE. The mineralogical composition of the pottery samples and comparison of the investigated pottery with thermally treated local clay indicated firing temperatures in the range from 600 to 800 degrees C. Two different types of white pigments were identified in white incrusted decorations: calcium carbonate and bone white (composed of crushed bones). This is the first evidence of the use of bones for decorations in pottery of the Vinca culture from the excavation site Plocnik. In addition to this, it was revealed that the potters used the iron reduction technique for obtaining black decorations

Ultrasound and shacking-assisted water-leaching of anions and cations from fly ash

Two mechanical extraction techniques were used for the extraction of environmentaly interesting components of coal fly ash: shaking, during which the extraction process lasted from 6 up to 24 h, and sonication that lasted from 15 up to 60 min, using water as extractant. The concentration of anions in fly ash extracts was determined by ion chromatography, while atomic absorption spectrometry was used for determination of: As, Pb, Cd, Ni, Cr, Zn, Cu, Fe, Mn and Al. The ultrasonication yielded slightly higher amounts of extracted anions as well as Pb, Al, Mn and Fe cations, while shaking-assisted extraction was more efficient for the Cr, As, Zn and Ni ions. The changes in pH value, particle size distribution within colloid solution, zeta potential and conductivity during ultrasound-assisted extraction were measured in order to explain changes that occur on the surface of fly ash particles contacting water and different processes (adsorption, ion exchange and flocculation) that develop under natural conditions. Principal Component Analysis was used for assessing the effect of observed process parameters. It is essential to evaluate quantity of these elements leachable from coal fly ash into the surface waters in natural conditions in order to prevent contamination of the environment

Pedological characteristics of open-pit Cu wastes and post-flotation tailings (Bor, Serbia)

To gain a better knowledge of mining areas and potential remediation processes, some characteristics (morphological, physical, chemical and microbiological) of soils formed on open-pit Cu mine waste (OPW) and Cu post-flotation tailings (PFT) dumps were investigated. Soil profiles and surface samples were studied. In general, the investigated soils are characterized by large proportion of coarse soil particles, degraded structure, low humus content, low pH, high As and Cu concentrations, and low soil microbial activity. In all investigated profiles there is no recognizable topsoil layer containing in situ formed humus probably due to soil age, lack of plant cover and organic litter, as well as other unfavorable soil conditions. The specificity of investigated soils is an irregular distribution of some soil characteristics (porosity, humus content, microbiological activity) over depth, which is a result of their technogenic origin. By establishing correlations between the studied surface sample parameters, using principal component analysis (PCA), poorer aggregate properties of PFT than of OPW soils were found, resulting most likely from aggressive mining, i.e., flotation processes. Both OPW and PFT soils compared with control natural soils are characterized by lower clay and humus content, and poorer aggregate properties

Radioactivity of sand from several renowned public beaches and assessment of the corresponding environmental risks

The radiological risk due to the presence of natural and man-made radionuclides in beach sands from several renowned seaside and riverbank public beaches was estimated in this study. The exposure levels to terrestrial radiation of the beaches were determined, as well as hazards due to human use of the analyzed sands in industry and in building constructions. Specific radionuclides concentrations in the sand samples were determined by standard gamma-spectrometry. The corresponding radiation hazards arising due to the use of sand as a building material were estimated by three different radiological hazard indices. The total absorbed gamma dose rate in the air was determined and the corresponding annual effective dose outdoors was estimated. The obtained data are relevant both from human health and environmental monitoring aspects

Pedological characteristics of open-pit Cu wastes and post-flotation tailings (Bor, Serbia)

To gain a better knowledge of mining areas and potential remediation processes, some characteristics (morphological, physical, chemical and microbiological) of soils formed on open-pit Cu mine waste (OPW) and Cu post-flotation tailings (PFT) dumps were investigated. Soil profiles and surface samples were studied. In general, the investigated soils are characterized by large proportion of coarse soil particles, degraded structure, low humus content, low pH, high As and Cu concentrations, and low soil microbial activity. In all investigated profiles there is no recognizable topsoil layer containing in situ formed humus probably due to soil age, lack of plant cover and organic litter, as well as other unfavorable soil conditions. The specificity of investigated soils is an irregular distribution of some soil characteristics (porosity, humus content, microbiological activity) over depth, which is a result of their technogenic origin. By establishing correlations between the studied surface sample parameters, using principal component analysis (PCA), poorer aggregate properties of PFT than of OPW soils were found, resulting most likely from aggressive mining, i.e., flotation processes. Both OPW and PFT soils compared with control natural soils are characterized by lower clay and humus content, and poorer aggregate properties

Physicochemical characterisation of pottery from the Vinča culture, Serbia, regarding the firing temperature and decoration techniques

A study of decorated Neolithic pottery samples from excavation site Pločnik, Serbia, was performed using X-ray powder diffraction (XRPD), Fourier transform infrared (FTIR) and X-ray fluorescence (XRF) spectroscopy. Investigated samples belong to the era of the Vinča culture which existed at the central Balkan region from mid VI until the first half of V millennium BCE. The mineralogical composition of pottery samples and comparison of investigated pottery with thermally treated local clay indicated firing temperature in the range from 600 to 800°C. Two different types of white pigments have been identified in white incrusted decorations: calcium carbonate and Bone White (composed of crushed bones). This is the first evidence of use of bones for decorations in Vinča culture pottery from excavation site Pločnik. In addition to this, it was revealed that the potters used the iron reduction technique for obtaining the black decorations. [Projekat Ministartsva nauke Republike Srbije, br. 177021 I br. 177012

JSCS–3847 Original scientific paper

Radioactivity of sand from several renowned public beaches and assessment of the corresponding environmental risk

Physicochemical investigation of some archaeometallurgical findings from locality Kmpije (Bor, Serbia)

Preliminary results of physicochemical investigation of some archaeometallurgical findings from Kmpije locality in vicinity of Bor (Serbia) are presented in this paper. Ancient samples of prehistoric origin were investigated using different instrumental analytic methods-chemical, differential thermal, X-ray diffraction, and energy dispersive X-ray fluorescence analysis. Obtained results indicate to the presence of ancient metallurgical activities, so locality Kmpije may be considered as an archaeometallurgical site, which should be investigated more in future for more precise details

The potential of ball-milled Serbian natural clay for removal of heavy metal contaminants from wastewaters: Simultaneous sorption of Ni, Cr, Cd and Pb ions

The influence of mechanical milling of natural Serbian clay on removal of heavy metals from an aqueous medium was investigated. The simultaneous sorption of the 4 toxic heavy metals (Ni, Cr, Cd and Pb), which are often present together in numerous polluting spills and in agrochemicals was evaluated. Microstructural and morphological changes in the ball-milled clay were characterized by X-ray diffraction (XRD), particle size distribution (PSD) and scanning electron microscopy (SEM). Induced changes in microstructure were correlated to the cation exchange capacity (CEC), determined by the EPA Method 9081. The CEC value has increased from 77 meq/100 g for the unmilled clay, to 95 meq/100 g for the milled clay. Regarding the untreated clay, the cation competition reveal some differences in their sorption: complete sorption (about 98% of the initial concentration) was achieved for Cr and Pb, while about 19% of the initial concentration of Cd and Ni still persist in the solution. The order of affinity of the metal ions is Pb approximate to Cr GT Cd approximate to Ni and it has not changed upon milling. (C) 2013 Elsevier Ltd and Techna Group S.r.l. All rights reserved