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The paper presents a comparative micromorphological analysis of the range of soil materials used to make the pottery of the hilly Galilee during the Roman period, and the ceramic products made from these materials. The four soil units that served as raw material for most of the pottery made in this period and region are examined along with pottery derived from each of them. For each soil unit, the soil characteristics and processes are described, followed by a presentation of the micromorphological characteristics of the soil material and those of the pottery made from that material. The contribution of the aeolian dust component to the soil materials is discussed as well as the identification of the tempering materials (nonplastics or other soil materials) added to the pottery paste. The study demonstrates the close correlation in microfabric between the pottery and original soil materials, sheds light on the raw material selection and modification practices of the potters of Roman Galilee, and has significant implications for provenance studies, using chemical analysis, on the pottery of this period and region. © 2002 Wiley Periodicals, Inc. 相似文献
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M. Mikolajewski T. Tomov M. Hajduk M. Cikala J. Osiwala C. Galan A. Zajczyk D. Kolev I. Iliev P. Marrese U. Munari T. Zwitter G. Galazutdinov F. Musaev A. Bondar L. Georgiev C. T. Bolton R. M. Blake W. Pych 《Astrophysics and Space Science》2005,296(1-4):451-455
High-resolution spectroscopy during the eclipse of EE Cep was obtained and presented for the first time. The star’s spectroscopic
behaviour can be roughly interpreted as a partial eclipse of the high luminosity Be primary and its emitting gaseous ring
by the semi-transparent gaseous envelope around an invisible, opaque secondary, most probably a dark disk.
This paper is based on spectroscopic observations from Asiago (Italy), DDO (Canada), Rozhen (Bulgaria), SPM (Mexico), Terskol
(Russia) and Torun (Poland) observatories. 相似文献
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A common assumption of ground water models formulated using a block-centered finite-difference method is that a well is located at the center of a cell regardless of its actual location. Due to this assumption, errors are introduced in the spatial distribution of simulated heads. This paper presents an alternative approach for assigning the pumping rates of wells that are located off cell centers. This approach consists of assigning the pumping rate not only to the cell in which the well is located but also to adjacent cells, taking into account the length of the well screen, the hydraulic conductivity, and the distance from the well to the center of its cell. The advantage of this alternative approach over the conventional one is illustrated with a test problem of a synthetic aquifer. Statistical measures of error indicate a much better model fit when pumping rates of wells are distributed over several cells. 相似文献
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Escudero Christian R. Ramirez Gaytan Alejandro Zamora Camacho Araceli Preciado Adolfo Flores Karen L. Gomez Hernandez Adan 《Natural Hazards》2022,110(1):247-267
Natural Hazards - We performed a seismic vulnerability assessment that involves geotechnical and building structure analysis for Puerto Vallarta, Mexico, a city located along the pacific coast.... 相似文献
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南极、北极和青藏高原作为地球的"三极"是全球变化的敏感区和研究热点.随着天空地一体化对地观测技术的快速发展,三极时空信息呈现出海量、高时效、多维度的大数据特征.但由于缺乏有效的可视化手段,这些数据很难被非科研人员理解和认知.如何面向不同人群,快速直观地展示三极最新科学发现所产生的时空数据,已成为数据可视化研究迫切需要解... 相似文献
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Lyra Andre Tavares Priscila Chou Sin Chan Sueiro Gustavo Dereczynski Claudine Sondermann Marcely Silva Adan Marengo José Giarolla Angélica 《Theoretical and Applied Climatology》2018,132(1-2):663-682
Theoretical and Applied Climatology - The objective of this work is to assess changes in three metropolitan regions of Southeast Brazil (Rio de Janeiro, São Paulo, and Santos) based on the... 相似文献
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Results of the analysis of 3261 radar meteor head echoes observed during the Orionid and Lyrid periods by the high-power radar of the Springhill Meteor Observatory are given. Dependence of the occurence of head echoes on the geometrical factors and physical properties of the meteoroids has been studied. Increas of the head echo rates with the elevation of the shower radiant and with the velocity of meteoroids has been observed. 相似文献
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M. Hajduk Albert A. Zijlstra P. A. M. van Hoof J. A. Lopez J. E. Drew A. Evans S. P. S. Eyres K. Gesicki R. Greimel F. Kerber S. Kimeswenger M. G. Richer 《Monthly notices of the Royal Astronomical Society》2007,378(4):1298-1308
CK Vul is classified as, amongst others, the slowest known nova, a hibernating nova or a very late thermal pulse object. Following its eruption in ad 1670, the star remained visible for 2 yr. A 15-arcsec nebula was discovered in the 1980s, but the star itself has not been detected since the eruption. We here present radio images which reveal a 0.1-arcsec radio source with a flux of 1.5 mJy at 5 GHz. Deep Hα images show a bipolar nebula with a longest extension of 70 arcsec, with the previously known compact nebula at its waist. The emission-line ratios show that the gas is shock-ionized, at velocities >100 km s−1 . Dust emission yields an envelope mass of ∼5 × 10−2 M⊙ . Echelle spectra indicate outflow velocities up to 360 km s−1 . From a comparison of images obtained in 1991 and 2004 we find evidence for expansion of the nebula, consistent with an origin in the 1670 explosion; the measured expansion is centred on the radio source. No optical or infrared counterpart is found at the position of the radio source. The radio emission is interpreted as thermal free–free emission from gas with T e ∼ 104 K . The radio source may be due to a remnant circumbinary disc, similar to those seen in some binary post-AGB stars. We discuss possible classifications of this unique outburst, including that of a sub-Chandrasekhar mass supernova, a nova eruption on a cool, low-mass white dwarf or a thermal pulse induced by accretion from a circumbinary disc. 相似文献