Fast large-scale reionization simulations     

Rajat M. Thomas  Saleem Zaroubi  Benedetta Ciardi  reas H. Pawlik  Panagiotis Labropoulos  Vibor Jeli&#;  Gianni Bernardi  Michiel A. Brentjens  A. G. de Bruyn  Geraint J. A. Harker  Leon V. E. Koopmans  Garrelt Mellema  V. N. Pandey  Joop Schaye  Sarod Yatawatta 《Monthly notices of the Royal Astronomical Society》2009,393(1):32-48

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Non-parametric foreground subtraction for 21-cm epoch of reionization experiments     

Geraint Harker  Saleem Zaroubi  Gianni Bernardi  Michiel A. Brentjens  A. G. de Bruyn  Benedetta Ciardi  Vibor Jeli&#;  Leon V. E. Koopmans  Panagiotis Labropoulos  Garrelt Mellema  ré Offringa  V. N. Pandey  Joop Schaye  Rajat M. Thomas  Sarod Yatawatta 《Monthly notices of the Royal Astronomical Society》2009,397(2):1138-1152

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THE DETERMINATION OF FLUORINE BY PROTON INDUCED GAMMA RAY EMISSION SPECTROMETRY (PIGE) IN EIGHTEEN CHINESE STANDARD REFERENCE SAMPLES OF STREAM SEDIMENTS, SOILS AND ROCKS: GSD 9-12, GSS 1-8 AND GSR 1-6     

Iwan ROELANDTS  Guy ROBAYE  Panagiotis ALOUPOGIANNIS  Georges WEBER  Jeanne-Marie DELBROUCK-HABARU 《Geostandards and Geoanalytical Research》1987,11(1):79-80

Eighteen new Chinese standard reference samples (including stream sediments, soils and rocks) have been analysed by an automated proton induced gamma ray emission (PIGE) method for fluorine. Results of determinations are reported and are generally in good agreement with the "usable values" previously published.  相似文献   

Identification of lime plaster in prehistory using petrographic methods: A review and reconsideration of the data on the basis of experimental and case studies     

Panagiotis Karkanas 《Geoarchaeology》2007,22(7):775-796

Most prehistoric plasters and mortars consist of very small amounts of burnt lime mixed with anthropogenic debris, soil, and sediment. To solve the problem of identification of such small amounts of lime in impure lime plasters, a series of experimental plasters were prepared and studied with petrographic methods. Samples of living floors from five prehistoric sites in Greece were also reanalyzed under the light of the experimental findings and compared with natural calcareous sediment. The most promising features for identifying lime are transitional textures of partially carbonized slaked lime that can be observed in the lime lumps and the binding matrix. They are usually in the form of ill‐crystallized portlandite and calcite mixtures or cryptocrystalline calcite. Well‐reacted calcitic groundmass, shrinkage fractures, and occasionally colloidal forms are also additional indications. The present experimental study shows that lime could be easily produced by heating porous, soft calcareous materials. This would probably account for the very frequent use (in small quantities) of lime in Greek prehistory. Plaster and mortars were made by mixing damp anthopogenic dirt as aggregate and fragments of quicklime, a technique known as “hot mixing.” © 2007 Wiley Periodicals, Inc.  相似文献   

Erratum to: A cervelleite-like mineral and other Ag-Cu-Te-S minerals [Ag2CuTeS and (Ag,Cu)2TeS] in gold-bearing veins in metamorphic rocks of the Cycladic Blueschist Unit, Kallianou, Evia Island, Greece     

Panagiotis Christos Voudouris  Paul G. Spry  Gregory Aarne Sakellaris  Constantinos Mavrogonatos 《Mineralogy and Petrology》2011,103(1-4):179-179

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Is the Palea Kavala Bi–Te–Pb–Sb ± Au district, northeastern Greece, an intrusion-related system?     

Andrew P. Fornadel  Paul G. Spry  Vasilios Melfos  Michael Vavelidis  Panagiotis Ch. Voudouris 《Ore Geology Reviews》2011,39(3):119-133

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Conditions of formation of the Mavrokoryfi high-sulfidation epithermal Cu�CAg�CAu�CTe mineralization (Petrota Graben, NE Greece)     

Panagiotis Christos Voudouris 《Mineralogy and Petrology》2011,101(1-2):97-113

The Mavrokoryfi Cu?CAg?CAu?CTe prospect, northeastern Greece, consists of atypical, high-sulfidation mineralization where precious metals were introduced contemporaneously with advanced argillic alteration from magmatic vapors. It occurs as veins of massive sulfides in zones of silicic and advanced argillic alteration spatially associated with an andesitic lava dome and hyaloclastites. Mineralogical data demonstrate an unusual ore and gangue mineralogy that is compatible with formation under very oxidizing conditions (logfO₂ values of >?31.8) at temperatures of 200°C to 250°C. Oxidizing conditions favored the formation of hypogene lead sulfates (anglesite and barian celestite) instead of galena. Selenian acanthite, cadmian freibergite, and argentian goldfieldite are the main carriers of silver in the deposit and are reported in Greece for the first time. They were deposited at logfS₂ of ?9 to ?7 and logfTe₂ values of ?9 to ?12.5 (250°C). Ag-poor goldfieldite at Mavrokoryfi has up to 3.7 apfu Te and is the most Te-rich goldfieldite yet reported. The mineralization is accompanied by aluminum?Cphosphate?Csulfate minerals of magmatic-hydrothermal origin and an unusual Pb-enrichment. Ore-forming components were likely derived from andesite porphyries.  相似文献   

Consistency of seven different GNSS global ionospheric mapping techniques during one solar cycle   总被引：1，自引：0，他引：1  

David Roma-Dollase  Manuel Hernández-Pajares  Andrzej Krankowski  Kacper Kotulak  Reza Ghoddousi-Fard  Yunbin Yuan  Zishen Li  Hongping Zhang  Chuang Shi  Cheng Wang  Joachim Feltens  Panagiotis Vergados  Attila Komjathy  Stefan Schaer  Alberto García-Rigo  José M. Gómez-Cama 《Journal of Geodesy》2018,92(6):691-706

In the context of the International GNSS Service (IGS), several IGS Ionosphere Associated Analysis Centers have developed different techniques to provide global ionospheric maps (GIMs) of vertical total electron content (VTEC) since 1998. In this paper we present a comparison of the performances of all the GIMs created in the frame of IGS. Indeed we compare the classical ones (for the ionospheric analysis centers CODE, ESA/ESOC, JPL and UPC) with the new ones (NRCAN, CAS, WHU). To assess the quality of them in fair and completely independent ways, two assessment methods are used: a direct comparison to altimeter data (VTEC-altimeter) and to the difference of slant total electron content (STEC) observed in independent ground reference stations (dSTEC-GPS). The main conclusion of this study, performed during one solar cycle, is the consistency of the results between so many different GIM techniques and implementations.  相似文献   

Mineralogical, stable isotope, and fluid inclusion studies of spatially related porphyry Cu and epithermal Au-Te mineralization, Fakos Peninsula, Limnos Island, Greece     

Andrew P. Fornadel  Panagiotis Ch. Voudouris  Paul G. Spry  Vasilios Melfos 《Mineralogy and Petrology》2012,105(1-2):85-111

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Decadal scale variability of sea surface temperature in the Mediterranean Sea in relation to atmospheric variability     

Nikolaos Skliris  Sarantis Sofianos  Athanasios Gkanasos  Anneta Mantziafou  Vasilis Vervatis  Panagiotis Axaopoulos  Alex Lascaratos 《Ocean Dynamics》2012,62(1):13-30

Twenty-four years of AVHRR-derived sea surface temperature (SST) data (1985–2008) and 35 years of NOCS (V.2) in situ-based SST data (1973–2008) were used to investigate the decadal scale variability of this parameter in the Mediterranean Sea in relation to local air–sea interaction and large-scale atmospheric variability. Satellite and in situ-derived data indicate a strong eastward increasing sea surface warming trend from the early 1990s onwards. The satellite-derived mean annual warming rate is about 0.037°C year^–1 for the whole basin, about 0.026°C year^–1 for the western sub-basin and about 0.042°C year^–1 for the eastern sub-basin over 1985–2008. NOCS-derived data indicate similar variability but with lower warming trends for both sub-basins over the same period. The long-term Mediterranean SST spatiotemporal variability is mainly associated with horizontal heat advection variations and an increasing warming of the Atlantic inflow. Analysis of SST and net heat flux inter-annual variations indicates a negative correlation, with the long-term SST increase, driving a net air–sea heat flux decrease in the Mediterranean Sea through a large increase in the latent heat loss. Empirical orthogonal function (EOF) analysis of the monthly average anomaly satellite-derived time series showed that the first EOF mode is associated with a long-term warming trend throughout the whole Mediterranean surface and it is highly correlated with both the Eastern Atlantic (EA) pattern and the Atlantic Multidecadal Oscillation (AMO) index. On the other hand, SST basin-average yearly anomaly and NAO variations show low and not statistically significant correlations of opposite sign for the eastern (negative correlation) and western (positive correlation) sub-basins. However, there seems to be a link between NAO and SST decadal-scale variations that is particularly evidenced in the second EOF mode of SST anomalies. NOCS SST time series show a significant SST rise in the western basin from 1973 to the late 1980s following a large warming of the inflowing surface Atlantic waters and a long-term increase of the NAO index, whereas SST slowly increased in the eastern basin. In the early 1990s, there is an abrupt change from a very high positive to a low NAO phase which coincides with a large change in the SST spatiotemporal variability pattern. This pronounced variability shift is followed by an acceleration of the warming rate in the Mediterranean Sea and a change in the direction (from westward to eastward) of its spatial increasing tendency.  相似文献