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51.
The newly developed lexsyg system by Freiberg Instruments is a versatile luminescence reader, suited for research on the luminescence of materials, fundamental research in luminescence dating, but also for routine mass measurements in retrospective dosimetry as well as in dating application. The 80 sample storage wheel is disconnected from the measurement chamber and therefore crosstalk of optical stimulation is absent and cross-irradiation is negligible from the α- and β-sources, which are providing very uniform irradiations, with the latter especially designed for radiofluores-cence (RF) measurement. Optical excitation sources and filter wheels to vary detection wavelengths can be programmed to change at almost any time within measurement sequences, including the auto-mated change of an optional wheel holding up to four different detectors. Thermoluminescence meas-urements and preheating are possible with a versatile heater, which can be programmed for linear or non-linear heating or cooling, as well as holding a temperature constant. Rates as well as durations can be varied, together with individual ramping, staging and cooling for an almost unlimited number of steps. Violet- and IR-lasers, green and blue LED-arrays can be operated in continuous (CW) or modulated mode (linear/non-linear), and optionally for pulsed as well as time resolved luminescence detection. Six arrays of power LEDs allow the simulation of different bleaching regimes (‘solar simu-lator’), while luminescence detection can be achieved by a variety of photomultiplier tubes and by CCD cameras for spatially resolved measurements and luminescence spectra. 相似文献
52.
Previous exhaustive analysis of the remains at Bois Laiterie Cave resulted in the classification of this site as a Magdalenian hunting camp. However, during recent analysis of usewear-traces on selected artefacts, one of the authors [KS] noticed in the collection numerous backed points which are rather untypical for the classical Magdalenian. In light of this, a typological and technological reinvestigation of the Bois Laiterie assemblage was undertaken. Here, we present the results of this investigation and the traceological analysis. Further, implications of these results for the interpretation of the chronological, archaeo-cultural and functional position of the Bois Laiterie site within the context of the north-western European Late Glacial are discussed. 相似文献
53.
Kyriaki Polikreti Joanne M.A. Murphy Vasilike Kantarelou Andreas Germanos Karydas 《Journal of archaeological science》2011
In recent years there has been a growing interest in Mycenaean glass among archaeologists and scientists. Scholars have traditionally thought that all Mycenaean glass was imported either in finished form or as ingots and simply shaped or worked at the Mycenaean sites. Chemical studies of other Mycenaean glass (50 and 43) support the hypothesis that glass was imported into Mycenaean Greece, but there is also indication for glass production in mainland Greece at the palace of Thebes (Nikita and Henderson, 2006). There is no evidence for glass making or working at the Palace of Pylos, yet there is an abundance of glass beads there. The aim of this paper is to identify the technology and source for the glass of these beads and thus to ascertain how Pylos was connected to the broader Mycenaean and Mediterranean economies. The composition of the glasses was determined by means of portable XRF analysis and compared to that of other Late Bronze Age glasses from Egypt, Mesopotamia and mainland Greece. Four blue beads coloured with cobalt and one blue bead coloured with copper have Ti and Zr compositions consistent with an Egyptian origin of manufacture while five other beads show Ti and Zr concentrations consistent with a Mesopotamian origin (Shortland et al., 2007). Based on the dearth of Egyptian and Mesopotamian imports in Pylos, the presented data support the hypothesis that Pylos was receiving via internal Greek trade routes foreign-produced glass, which may have been worked abroad or in Greece. 相似文献
54.
Hendrik J. Bruins J. Alexander MacGillivray Costas E. Synolakis Chaim Benjamini Jörg Keller Hanan J. Kisch Andreas Klügel Johannes van der Plicht 《Journal of archaeological science》2008
The explosive eruption at Santorini in the Aegean Sea during the second millennium BCE was the largest Holocene volcanic upheaval in the Eastern Mediterranean region. The eruption was disastrous for the Minoan settlements at Santorini, but the effect on human society in the neighbouring islands and regions is still clouded in uncertainty. Tsunami generation was suggested, but comparatively little evidence was found. The lack of firm tsunami traces is particularly puzzling in Crete with its coastal settlements of the Late Minoan IA period, during which the Santorini eruption occurred. Here, we report the discovery of extensive geoarchaeological tsunami deposits at Palaikastro in north-eastern Crete. These deposits are characterized by a mixture of geological materials, including volcanic Santorini ash, and archaeological settlement debris. Various tsunami signatures were identified: (1) erosional contact with the underlying strata, (2) volcanic ash intraclasts in the lower part of the deposit, (3) reworked building stone material in the lower part of the deposit, (4) individual marine shells, (5) marine micro-fauna, (6) imbrication of rounded beach pebbles, settlement debris, ceramic sherds and even bones, (7) multi-modal chaotic composition. Late Minoan human settlement activities at Palaikastro provided architectural and stratigraphic frameworks in space and time that recorded and preserved tsunami evidence as geoarchaeological deposits. Such stratigraphic resolution and preservation may not occur in the natural landscape. Volcanic ash transported by wind from Santorini south-east to Crete preceded the tsunami. Geological, archaeological and radiocarbon dating criteria all converge, indicating that the tsunami deposits are coeval with the Minoan Santorini eruption. Field evidence suggests that tsunami waves at Palaikastro were at least 9 m high. Inverse tsunami modeling was attempted, based on these newly discovered tsunamigenic deposits. The initial wave in the generation region at Santorini that best fits the stratigraphic data is a wave with +35 to −15 m initial amplitude and a crest length of about 15 km. 相似文献
55.
Florian Ströbele Thomas Wenzel Andreas Kronz Ludwig H. Hildebrandt Gregor Markl 《Archaeological and Anthropological Sciences》2010,2(3):191-215
Here, we present detailed electron microprobe analyses and age data of high-medieval lead–silver smelting slags. The mineral
composition data provide a database of all silicate and oxide phases in the slag. Bulk chemistry as well as mineral composition
is used to reconstruct liquidus, solidus, and viscosity of the slag melt. By calculating the mass balance of the smelting
process, a mass ratio of the various compounds used in the smelting process is determined. Through this we were able to discriminate
qualitatively between non-ferrous metal smelting slags and bloomery slags. We also report a new type and process of silver
production in which argentiferous galmei (zinc carbonate) was used as a main silver ore together with galena. The results
indicate a sophisticated high-medieval smelting technology, in which a slag with a low liquidus and a low viscosity was created. 相似文献
56.
Andreas Woyke 《Berichte zur Wissenschaftsgeschichte》2008,31(1):58-67
Reflections about an embedding of nanotechnology in a continuum of the history of science and technology. Nanotechnology is not a completely new technology, we can rather understand it as a continuation and extension of chemical technology. Along this line, it is not only problematic to characterize nanotechnology as a new ‘key technology’ but also the definition of nanotechnology as looking at a particular causality between properties and dimensions of materials seems hardly new. For embedding nanotechnology in such a greater historical context, the development of colloid chemistry at the beginning of the 20th century by Richard Zsigmondy and Wolfgang Ostwald is shown as an important reference point. Modern theories of supramolecular chemistry as those constituted by Jean‐Marie Lehn and others refer to this line of research in colloid chemistry and lead currently to scientific foundations of some nanotechnological fields. The historical embedding of nanotechnology can hence be used as a contribution for a more realistic evaluation of the technological possibilities as well as for a critical estimation of technological visions. 相似文献
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