H. Papaefthymiou - Academia.edu (original) (raw)

Papers by H. Papaefthymiou

Journal of African Earth Sciences, 2019

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Journal of Radioanalytical and Nuclear Chemistry, 2006

ABSTRACT Four different bottled water brands sold in Greece in the winter of 2001-2002 were analy... more ABSTRACT Four different bottled water brands sold in Greece in the winter of 2001-2002 were analyzed for a wide range of chemical elements, using neutron activation analysis (NAA). The elements Na and Br were determined instrumentally (INAA), whereas the other metals and trace elements radiochemically (RNAA). The results indicated that the mean level of all the elements determined in the samples were well within the European Union (EU) directive on drinking water and accomplish the drinking water standards of the World Health Organisation (WHO) as well as of the Food and Drug Administration (FDA).

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Radiation Effects, 1985

ABSTRACT

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Journal of Radioanalytical and Nuclear Chemistry, 2007

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Measurements of indoor radon (Rn) concentrations were carried out by using LR-115 II solid state ... more Measurements of indoor radon (Rn) concentrations were carried out by using LR-115 II solid state nuclear track detectors (SSNTD). One hundred forty detectors were placed randomly in Patras houses for two periods of three months exposure, from December 1996 to November 1997. The observed mean radon values compared with the standard recommended values are low, while the maximum recorded value is found to be within the limits. The influence of seasonal variation as well the distance from the ground on radon level were also investigated.

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Journal of Radioanalytical and Nuclear Chemistry

The levels and depth distributions of the natural radionuclides 238U, 232Th, 226Ra, 40K and the m... more The levels and depth distributions of the natural radionuclides 238U, 232Th, 226Ra, 40K and the man-made 137Cs were analyzed by γ-ray spectrometry, while the concentrations of 26 chemical elements were measured by INAA in sediment samples collected from the organic mud layer that covers the Keratsini–Psitalia strait, Saronikos gulf (Greece). The average activity concentration values of 226Ra, 232Th and 40K were lower when compared, whereas that of 238U was comparable to the average Greek and world values. The elemental contamination of the sediments was estimated on the basis of the calculated EF values. The results revealed high EF values of As, Br, Cr, Ni, Sb, Se, Zn ranging from 160 for Br to 10 for Cr, whose main sources are probable related to contaminated sewage outfall from the area of Athens and the Piraeus Harbour.

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International Journal of …, 2009

The present study aims to elucidate the depositional environment of Seam I in the Megalopolis Bas... more The present study aims to elucidate the depositional environment of Seam I in the Megalopolis Basin, Southern Greece, using existing geological data supported by maceral and mineralogical analyses, as well as by natural radioactivity determinations. Very high pyrite and uranium ...

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Radiation Effects

ABSTRACT

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X-Ray Spectrometry

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Bulletin of the Geological Society of Greece

The Corinth rift is counted among the most active tectonic grabens in the world, with extension r... more The Corinth rift is counted among the most active tectonic grabens in the world, with extension rates up to 15 mm/yr (Western part). These high extension rates are associated with very strong seismic events that are, occasionally, responsible for submarine mass movements. These movements, their consequential bottom currents, and the differential river-discharging sediment accumulation in the whole gulf, strongly affect the modern marine sedimentary processes. The definition and understanding of these processes is the main aim of this project. This is attempted through via sedimentological, mineral and geochemical analyses on sediment samples from two ~1.1 m long, sediment cores from a WE submarine canyon (10 km long, 3 km wide) that lies in the Western tip of the gulf. The general sedimentation motif reveals the presence of hemipelagic deposits which are occasionally interrupted by sandy turbidites. Occasionally, these turbidites seem to have seismic origin. The sedimentation rates ...

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Radioprotection, 2005

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ABSTRACT Natural radionuclides and 137 Cs activity concentrations were measured in marine sedimen... more ABSTRACT Natural radionuclides and 137 Cs activity concentrations were measured in marine sediments collected from the most representative areas of Patras and Corinth Gulfs. Their regional distributions depend on geological, geochemical and anthropogenic (mining activities) factors. Introduction -The total amount of radionuclides and 137 Cs in the marine sediments depends on many geological, geochemical, biological and an-thropogenic factors and processes such as the geology of the surrounding land, mineral composition, content of organic matter, sedimentation rate, resuspension, texture of the sediment, etc. In this paper the 238 U, 232 Th, 226 Ra, 40 K and 137 Cs specific activities in the marine sediments of Pa-tras and Corinth Gulfs and their possible relation to the above mentioned factors and processes are presented. Study area -The Gulfs of Patras and Corinth represent a continuous system of WNW-ESE trending basins in the Central Greece. Sampling stations were chosen to cover the most representative areas of the two gulfs as detailed below: (i) Antikyra Bay (ANT): Located at the northern margin of the Gulf of Corinth. This region has been extensively sampled and investigated in previous years [1], as an aluminum processing plant (ALUMINIO HELLAS) discharges bauxitic red mud tailings into this Bay. The discharged red mud tailings have resulted in the formation of a surface layer which covers the seafloor. It should be noted that the baux-ites usually contain significant amounts of uranium and thorium as result of their formation. (ii) Galaxidi (GAL) and Kirra (KIR) coastal areas are located at the Itea Bay at the northern margin of the Gulf of Corinth. (iii) Eratini Bay (ERA) and Ag. Pantes (AGP) coastal areas are also situated at the northern margin of the Gulf of Corinth. ERA 5 and 6 sampling points are located in the vicinity of the submarine fan delta of the Eratini seasonal river. (iv) Basin of the Gulf of Corinth (CORBAS): a reference sampling point for background levels which is located at the central basin of the Gulf at a water depth of 850m. (v) Messolonghi Lagoon (MES) is located in the northern coast of the Patras Gulf and constitutes the southernmost part of the Messolonghi-Aetoliko lagoon complex, which is the most extended lagoon system in Greece. This complex is part of the same water course in the drainage basin of the Acheloos and Evinos rivers. The northern part of the drainage basin was heavily contaminated by the Chernobyl fallout. (vi) The Patras harbour (PATH) is located at (in) the southeastern coast of the Gulf of Patras. The Patras harbour due to its vicinity to Patras city (200.000 citizens), is contaminated with respect to harbour and urban activities. (vii) Basin of the Patras Gulf (PATBAS): a reference sampling point for background levels which is located at the basin of the Gulf in a water depth of 95m. Materials and Methods -Sediments were sampled using a 50x50x50cm box corer, a 3.0 m long gravity corer and a Day grab. The uppermost 2cm of all cores were subjected to a direct γ-ray spectrometry for specific activity measurements of 238 U, 232 Th, 226 Ra, 40 K and 137 Cs using a HPGe detector. Results and Discussion -The activities of 238 U, 232 Th, 226 Ra, 40 K and 137 Cs are shown in Table 1. The 238 U, 232 Th, 226 Ra and 40 K obtain

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Radiation Measurements, 2010

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Radiation Protection Dosimetry, 2013

Twenty soil profile samples and fourteen surface soil samples collected from the vicinity of the ... more Twenty soil profile samples and fourteen surface soil samples collected from the vicinity of the lignite-fired power plants in the Megalopolis basin (Greece) were analysed for their natural radionuclide concentration and (137)Cs, since fossil fuels are associated with naturally occurring radioactive materials and hence with radiological impact. No significant enhancement of surface soil radioactivity levels in the vicinity of lignite-fired plants was observed. A downcore decreasing trend of (137)Cs was observed in a number of cores reflecting its atmospheric origin, whereas the uniform distribution observed in a number of other cores gave information on the mechanical alteration of the soil. The average dose rate value was found to be 63 ± 22 nGy h(-1), while the annual average effective dose from the terrestrial gamma radiation was found to be 0.08 ± 0.03 mSv.

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Radiation Protection Dosimetry, 2008

Measurements of (226)Ra, (232)Th and (40)K activity concentrations in commercial granite tiles im... more Measurements of (226)Ra, (232)Th and (40)K activity concentrations in commercial granite tiles imported in Greece were performed using gamma-ray spectrometry. The activity concentration of (226)Ra, (232)Th and (40)K ranged from 1 to 434, 2 to 239 and 71 to 1576 Bq kg(-1), respectively. The calculated activity concentration index (I) values for all granite samples examined were found to be within the EC limit values for superficial and other materials with restricted use.

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Radiation Protection Dosimetry, 2011

The activity concentrations of the natural radionuclides (238)U, (226)Ra, (232)Th and (40)K were ... more The activity concentrations of the natural radionuclides (238)U, (226)Ra, (232)Th and (40)K were measured in soil samples collected from the Patras-Rion sub-basins (Southern Greece) and were found to be 28, 27, 30 and 483 Bq kg(-1), respectively. These values compare well with the average Greek and worldwide values for crustal soil and sedimentary rocks. The mean (226)Ra/(238)U activity ratio was close to 1, implying secular radioactive equilibrium in the uranium series. All soil samples have Ra(eq) values lower than the limit of 370 Bq kg(-1), indicating their safe use in brick production. The average annual terrestrial absorbed dose rate in air was 51±14 nGy h(-1), and the average annual effective dose 0.06±0.02 mSv y(-1), which is consistent with the average worldwide exposure to external terrestrial radiation outdoors (0.07 mSv y(-1)). Non-significant differences between soils with different age and depositional environments were found, which could be attributed to a common source of sediments.

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Radiation Effects and Defects in Solids, 1990

ABSTRACT

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Microchemical Journal, 2010

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Journal of Radioanalytical and Nuclear Chemistry, 2008

ABSTRACT Bulk deposition samples were collected on a monthly basis in Megalopolis city, located n... more ABSTRACT Bulk deposition samples were collected on a monthly basis in Megalopolis city, located near lignite power plants. A total of 23 elements (As, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, La, Mo, Na, Rb, Sb, Sc, Se, Ta, Tb, Th, U, Yb, Zn) were detected in the collected samples using INAA. The coal burning marker elements As and Se were found enriched in the collected samples together with Mo, Br, Sb, U and Zn. Factor analysis permitted the identification of four sources: re-suspended soil/road dust, lignite power plant, sea spray and traffic emissions. A wind direction effect on deposition rates of all elements (except rates of Na, Rb, Sb and Zn) was also found.

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Journal of Radioanalytical and Nuclear Chemistry, 2011

Page 1. A comparison between INAA and ICP-MS for the determination of element concentrations in m... more Page 1. A comparison between INAA and ICP-MS for the determination of element concentrations in marine sediments H. Papaefthymiou • G. Papatheodorou Received: 4 February 2011 Ó Akadémiai Kiadó, Budapest, Hungary 2011 ...

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Journal of African Earth Sciences, 2019

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Journal of Radioanalytical and Nuclear Chemistry, 2006

ABSTRACT Four different bottled water brands sold in Greece in the winter of 2001-2002 were analy... more ABSTRACT Four different bottled water brands sold in Greece in the winter of 2001-2002 were analyzed for a wide range of chemical elements, using neutron activation analysis (NAA). The elements Na and Br were determined instrumentally (INAA), whereas the other metals and trace elements radiochemically (RNAA). The results indicated that the mean level of all the elements determined in the samples were well within the European Union (EU) directive on drinking water and accomplish the drinking water standards of the World Health Organisation (WHO) as well as of the Food and Drug Administration (FDA).

Bookmarks Related papers MentionsView impact

Radiation Effects, 1985

ABSTRACT

Bookmarks Related papers MentionsView impact

Journal of Radioanalytical and Nuclear Chemistry, 2007

Bookmarks Related papers MentionsView impact

Measurements of indoor radon (Rn) concentrations were carried out by using LR-115 II solid state ... more Measurements of indoor radon (Rn) concentrations were carried out by using LR-115 II solid state nuclear track detectors (SSNTD). One hundred forty detectors were placed randomly in Patras houses for two periods of three months exposure, from December 1996 to November 1997. The observed mean radon values compared with the standard recommended values are low, while the maximum recorded value is found to be within the limits. The influence of seasonal variation as well the distance from the ground on radon level were also investigated.

Bookmarks Related papers MentionsView impact

Journal of Radioanalytical and Nuclear Chemistry

The levels and depth distributions of the natural radionuclides 238U, 232Th, 226Ra, 40K and the m... more The levels and depth distributions of the natural radionuclides 238U, 232Th, 226Ra, 40K and the man-made 137Cs were analyzed by γ-ray spectrometry, while the concentrations of 26 chemical elements were measured by INAA in sediment samples collected from the organic mud layer that covers the Keratsini–Psitalia strait, Saronikos gulf (Greece). The average activity concentration values of 226Ra, 232Th and 40K were lower when compared, whereas that of 238U was comparable to the average Greek and world values. The elemental contamination of the sediments was estimated on the basis of the calculated EF values. The results revealed high EF values of As, Br, Cr, Ni, Sb, Se, Zn ranging from 160 for Br to 10 for Cr, whose main sources are probable related to contaminated sewage outfall from the area of Athens and the Piraeus Harbour.

Bookmarks Related papers MentionsView impact

International Journal of …, 2009

The present study aims to elucidate the depositional environment of Seam I in the Megalopolis Bas... more The present study aims to elucidate the depositional environment of Seam I in the Megalopolis Basin, Southern Greece, using existing geological data supported by maceral and mineralogical analyses, as well as by natural radioactivity determinations. Very high pyrite and uranium ...

Bookmarks Related papers MentionsView impact

Radiation Effects

ABSTRACT

Bookmarks Related papers MentionsView impact

X-Ray Spectrometry

Bookmarks Related papers MentionsView impact

Bulletin of the Geological Society of Greece

The Corinth rift is counted among the most active tectonic grabens in the world, with extension r... more The Corinth rift is counted among the most active tectonic grabens in the world, with extension rates up to 15 mm/yr (Western part). These high extension rates are associated with very strong seismic events that are, occasionally, responsible for submarine mass movements. These movements, their consequential bottom currents, and the differential river-discharging sediment accumulation in the whole gulf, strongly affect the modern marine sedimentary processes. The definition and understanding of these processes is the main aim of this project. This is attempted through via sedimentological, mineral and geochemical analyses on sediment samples from two ~1.1 m long, sediment cores from a WE submarine canyon (10 km long, 3 km wide) that lies in the Western tip of the gulf. The general sedimentation motif reveals the presence of hemipelagic deposits which are occasionally interrupted by sandy turbidites. Occasionally, these turbidites seem to have seismic origin. The sedimentation rates ...

Bookmarks Related papers MentionsView impact

Radioprotection, 2005

Bookmarks Related papers MentionsView impact

ABSTRACT Natural radionuclides and 137 Cs activity concentrations were measured in marine sedimen... more ABSTRACT Natural radionuclides and 137 Cs activity concentrations were measured in marine sediments collected from the most representative areas of Patras and Corinth Gulfs. Their regional distributions depend on geological, geochemical and anthropogenic (mining activities) factors. Introduction -The total amount of radionuclides and 137 Cs in the marine sediments depends on many geological, geochemical, biological and an-thropogenic factors and processes such as the geology of the surrounding land, mineral composition, content of organic matter, sedimentation rate, resuspension, texture of the sediment, etc. In this paper the 238 U, 232 Th, 226 Ra, 40 K and 137 Cs specific activities in the marine sediments of Pa-tras and Corinth Gulfs and their possible relation to the above mentioned factors and processes are presented. Study area -The Gulfs of Patras and Corinth represent a continuous system of WNW-ESE trending basins in the Central Greece. Sampling stations were chosen to cover the most representative areas of the two gulfs as detailed below: (i) Antikyra Bay (ANT): Located at the northern margin of the Gulf of Corinth. This region has been extensively sampled and investigated in previous years [1], as an aluminum processing plant (ALUMINIO HELLAS) discharges bauxitic red mud tailings into this Bay. The discharged red mud tailings have resulted in the formation of a surface layer which covers the seafloor. It should be noted that the baux-ites usually contain significant amounts of uranium and thorium as result of their formation. (ii) Galaxidi (GAL) and Kirra (KIR) coastal areas are located at the Itea Bay at the northern margin of the Gulf of Corinth. (iii) Eratini Bay (ERA) and Ag. Pantes (AGP) coastal areas are also situated at the northern margin of the Gulf of Corinth. ERA 5 and 6 sampling points are located in the vicinity of the submarine fan delta of the Eratini seasonal river. (iv) Basin of the Gulf of Corinth (CORBAS): a reference sampling point for background levels which is located at the central basin of the Gulf at a water depth of 850m. (v) Messolonghi Lagoon (MES) is located in the northern coast of the Patras Gulf and constitutes the southernmost part of the Messolonghi-Aetoliko lagoon complex, which is the most extended lagoon system in Greece. This complex is part of the same water course in the drainage basin of the Acheloos and Evinos rivers. The northern part of the drainage basin was heavily contaminated by the Chernobyl fallout. (vi) The Patras harbour (PATH) is located at (in) the southeastern coast of the Gulf of Patras. The Patras harbour due to its vicinity to Patras city (200.000 citizens), is contaminated with respect to harbour and urban activities. (vii) Basin of the Patras Gulf (PATBAS): a reference sampling point for background levels which is located at the basin of the Gulf in a water depth of 95m. Materials and Methods -Sediments were sampled using a 50x50x50cm box corer, a 3.0 m long gravity corer and a Day grab. The uppermost 2cm of all cores were subjected to a direct γ-ray spectrometry for specific activity measurements of 238 U, 232 Th, 226 Ra, 40 K and 137 Cs using a HPGe detector. Results and Discussion -The activities of 238 U, 232 Th, 226 Ra, 40 K and 137 Cs are shown in Table 1. The 238 U, 232 Th, 226 Ra and 40 K obtain

Bookmarks Related papers MentionsView impact

Radiation Measurements, 2010

Bookmarks Related papers MentionsView impact

Radiation Protection Dosimetry, 2013

Twenty soil profile samples and fourteen surface soil samples collected from the vicinity of the ... more Twenty soil profile samples and fourteen surface soil samples collected from the vicinity of the lignite-fired power plants in the Megalopolis basin (Greece) were analysed for their natural radionuclide concentration and (137)Cs, since fossil fuels are associated with naturally occurring radioactive materials and hence with radiological impact. No significant enhancement of surface soil radioactivity levels in the vicinity of lignite-fired plants was observed. A downcore decreasing trend of (137)Cs was observed in a number of cores reflecting its atmospheric origin, whereas the uniform distribution observed in a number of other cores gave information on the mechanical alteration of the soil. The average dose rate value was found to be 63 ± 22 nGy h(-1), while the annual average effective dose from the terrestrial gamma radiation was found to be 0.08 ± 0.03 mSv.

Bookmarks Related papers MentionsView impact

Radiation Protection Dosimetry, 2008

Measurements of (226)Ra, (232)Th and (40)K activity concentrations in commercial granite tiles im... more Measurements of (226)Ra, (232)Th and (40)K activity concentrations in commercial granite tiles imported in Greece were performed using gamma-ray spectrometry. The activity concentration of (226)Ra, (232)Th and (40)K ranged from 1 to 434, 2 to 239 and 71 to 1576 Bq kg(-1), respectively. The calculated activity concentration index (I) values for all granite samples examined were found to be within the EC limit values for superficial and other materials with restricted use.

Bookmarks Related papers MentionsView impact

Radiation Protection Dosimetry, 2011

The activity concentrations of the natural radionuclides (238)U, (226)Ra, (232)Th and (40)K were ... more The activity concentrations of the natural radionuclides (238)U, (226)Ra, (232)Th and (40)K were measured in soil samples collected from the Patras-Rion sub-basins (Southern Greece) and were found to be 28, 27, 30 and 483 Bq kg(-1), respectively. These values compare well with the average Greek and worldwide values for crustal soil and sedimentary rocks. The mean (226)Ra/(238)U activity ratio was close to 1, implying secular radioactive equilibrium in the uranium series. All soil samples have Ra(eq) values lower than the limit of 370 Bq kg(-1), indicating their safe use in brick production. The average annual terrestrial absorbed dose rate in air was 51±14 nGy h(-1), and the average annual effective dose 0.06±0.02 mSv y(-1), which is consistent with the average worldwide exposure to external terrestrial radiation outdoors (0.07 mSv y(-1)). Non-significant differences between soils with different age and depositional environments were found, which could be attributed to a common source of sediments.

Bookmarks Related papers MentionsView impact

Radiation Effects and Defects in Solids, 1990

ABSTRACT

Bookmarks Related papers MentionsView impact

Microchemical Journal, 2010

Bookmarks Related papers MentionsView impact

Journal of Radioanalytical and Nuclear Chemistry, 2008

ABSTRACT Bulk deposition samples were collected on a monthly basis in Megalopolis city, located n... more ABSTRACT Bulk deposition samples were collected on a monthly basis in Megalopolis city, located near lignite power plants. A total of 23 elements (As, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, La, Mo, Na, Rb, Sb, Sc, Se, Ta, Tb, Th, U, Yb, Zn) were detected in the collected samples using INAA. The coal burning marker elements As and Se were found enriched in the collected samples together with Mo, Br, Sb, U and Zn. Factor analysis permitted the identification of four sources: re-suspended soil/road dust, lignite power plant, sea spray and traffic emissions. A wind direction effect on deposition rates of all elements (except rates of Na, Rb, Sb and Zn) was also found.

Bookmarks Related papers MentionsView impact

Journal of Radioanalytical and Nuclear Chemistry, 2011

Page 1. A comparison between INAA and ICP-MS for the determination of element concentrations in m... more Page 1. A comparison between INAA and ICP-MS for the determination of element concentrations in marine sediments H. Papaefthymiou • G. Papatheodorou Received: 4 February 2011 Ó Akadémiai Kiadó, Budapest, Hungary 2011 ...

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