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mechanism is affected of the chemical composition of the pozzolan as the greater the composition of alumina and silica along with the vitreous phase in the material, the better the pozzolanic reaction and strength display. More than 2,000 years ago, Greeks

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]. While several studies have been published regarding pigments and mortars from the Byzantine time [ 1 – 3 , 11 – 14 ], the analytical characterization of the Byzantine and post-Byzantine artefacts of Kastoria, northern Greece, is only sporadically

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Abstract  

The promise associated with early ancient DNA results has not been translated into routine techniques of value to archaeologists. The reasons for this are partly technical - ancient DNA analysis is an extremely difficult technique - and partly practical - ancient DNA analysis is often an after thought to an archaeological project. In this paper ancient human DNA analysis is briefly reviewed paying particular attention to specimens originating from Greek archaeological contexts. Problems commonly encountered during ancient DNA research are summarised and recommendations for future strategies in the application of ancient DNA in archaeology are proposed.

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Abstract  

In continuation, of an early study of trace metal /TM/ccontent of Greek lignites and power plant ashes, taken to assess mobilization of TM in Greece by the operation of power plants, new data are presented. Both power plant sites in Greece, i. e. /a/ Northern /Ptolemais, Kardia/, and /b/ Southern /Megalopolis/ have been examined for trace metal content in ashes and in locally used lignites. Instrumental neutron activation analysis /INAA/ was used to determine the content of about 30 minor and major elements. The uranium content of southern Greek lignites was found again to be exceptionally high. The new data are correlated with those of our previous investigation.

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Abstract  

Pilot ESR dating studies on geologically young calcitic sinters were carried out, aiming at assessment of the lower ESR dating range in characteristic Greek speleoenvironments. Five stalactites were dated, coming from an ancient mining gallery, idle for the last 2,500 years, found on Siphnos island (Aegean). The calculated ages range between 1.7-2.0 ka. Medium to low measured external dose rates (aprox. 900 Gy/a) and very low measured radioelement concentration in samples are very usual in the Mediterranean environments. The study concludes that ESR dating of speleothems younger than two millennia is practically unattainable. Some geoarchaeological implications of the obtained ages are discussed.

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Abstract  

Neutron activation analysis, in combination with multivariate analysis of the generated data, was used for the chemical characterization of prehistoric pottery from the Greek islands of Thera, Melos (islands with similar geology) and Crete. The statistical procedure which proved that Theran pottery could be distinguishable from Melian, is described. This discrimination, attained for the first time, was mainly based on the concentrations of the trace elements Sm, Yb, Lu and Cr. Also, Cretan imports to both Thera and Melos were clearly separable from local wares.

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Abstract  

The activity concentrations of 238U and 234U have been determined in groundwater samples of hot springs and deep wells in Northern Greece. The analysis was performed by alpha spectroscopy after pre-concentration and separation of uranium by cation exchange (Chelex 100 resin) and finally its electro-deposition on stainless steel discs. The uranium concentration in deep wells and springs varies strongly between 0.15 and 7.66 μg L−1 and the corresponding 238U and 234U activity concentrations between 1.82–95.3 and 1.70–160.1 mBq L−1, respectively. The obtained isotopic ratio 234U/238U varies between 0.95 and 1.74 indicating a disturbed radioactive equilibrium between the two uranium isotopes. In the studied waters uranium concentrations in solution decrease with increasing pH in the pH range between 7 and 9. This is attributed to the fact that at lower pH dissolution of soil minerals occurs and uranium which is adsorbed or forms solid solution with the geological matrix enters the aqueous phase. The strong dependence of the uranium concentration in the studied waters from the dissolution of the geological matrix is corroborated by the strong correlation of the uranium concentration with the electrical conductivity measured in the ground waters under investigation.

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Abstract  

Photon induced X-ray fluorescence is used at a medium sized Greek industrial city, to detect trace elements with 20≤Z≤40 in airborn particulates collected on filter papers.

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Abstract  

Most of the Greek lignite power plants have been installed in the area of Ptolemais, and a major part of them during the period 1981–1990. Aerosol filters collected in the first and the last years of the decade have been analysed for trace elements as well as for radioactivity (total beta) content. Analysis was performed by radioisotope excited X-ray fluorescence, and 17 elements were determined. A special interest is focused on lead concentrations, an element whose environmental concentrations are regulated by the Greek law; the results for lead were validated by atomic absorption spectrometry. Trace element and radioactivity levels were found significantly lower than the current limit. Enrichment factors and correlation among the analysed elements were also estimated.

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Abstract  

Instrumental Neutron Activation Analysis (NAA) has been applied for the determination of Ag and Sb in water column, sediment cores, and two marine organisms from Saronikos Gulf, Greece. Higher levels of Ag and Sb were found in the water column and cores from polluted areas of the Gulf as compared to those from unpolluted areas. No significant differences of Ag and Sb were found in the two marine organisms from all areas of Saronikos Gulf.

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