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91.
Nikolaos Zacharias Alexander Schwedt Jaume Buxeda i Garrigós Christodoulos T. Michael Hans Mommsen Vasilis Kilikoglou 《Journal of archaeological science》2007
In luminescence dating, the potassium concentration significantly contributes to the dose rate value in the age estimation. Within this study, fine-grain thermoluminescence dating has been applied on sherds of calcareous pottery of known age, excavated at a Roman site in Mallorca, Spain. For those of the samples that showed signs of severe potassium leaching, according to chemical and mineralogical examination, the thermoluminescence analysis provided overestimated dates. By using the known archaeological age of the samples, a corrected dose rate value can be estimated which provides the potassium concentration averaged for the burial period. Finally, a step-like model can then be used to estimate the fraction of the burial period after which most of the alteration effects took place. 相似文献
92.
Jesús M. González Pérez 《European Planning Studies》2007,15(1):29-50
This work analyses the main Spanish legislative and urban planning instruments, highlighting some of the most important structural problems of the current Spanish urban realities. The survey on legislation runs from the first Land Use Act of 1956 to the decentralization of the administration and the culmination of the transfer processes to the respective Spanish regions. Later, we study the complete well-structured hierarchy of urban planning instruments in use at present. Finally, we analyse how these and other factors have an influence on the capacity to control housing prices and on a lack of sustainability characterized by the excessive urbanizing use of the land. 相似文献
93.
94.
欣赏中国书法、篆刻,是一门学问。人们对于书法篆刻的兴趣和爱好,往往是出于对它们欣赏。其实,欣赏本身就是学习中不可缺少的实践活动。 相似文献
95.
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97.
The paper deals with dendrochronological and radiocarbon dating of subfossil trunks found in the basin of the Morava River.
The research into subfossil trunks had been conducted in the Czech Republic in the past but the research stopped in 2001.
160 records of measurements of subfossil, predominantly oak trunk samples, are preserved from that time. Three years ago the
research was reopened and again the most trunks were found in the basin of the Morava River. 92 samples of oak trunks and
7 samples of other tree species (poplar, elm, maple, beech) were taken from selected sites. The samples were processed in
compliance with the standard dendrochronological methodology. To date the samples, Czech, Austrian, Polish and German standard
chronologies were used. In cases when the dendrochronological dating was unsuccessful, the samples were sent for radiocarbon
dating. In total, 35 samples were dated, mainly by the radiocarbon method. Subfossil trunks from gravel pit Tovačov were dated
and classified into 4 different periods, the oldest being from 2780–2190 BC. In Osek nad Bečvou, the samples were taken from
two sites. Whereas from the 4 trunks taken in the river channel each was from a different period, the trunks from the gravel
pit come from 981–1015 AD. The trunks found in the Morava River basin near Strážnice were dated to the 10th–15th century. In the future, we expect to extend the amount of the acquired samples with the aim to create a link to the existing
standard chronology or to create a long floating average treering curve. 相似文献
98.
99.
María Gabriela Musaubach Anabela Plos María Del Pilar Babot 《Journal of archaeological science》2013,40(2):1186-1193
This paper presents, for the first time, a detailed study, from an archaeological perspective, of the morphological characteristics of the starch grains within the kernels of selected native wild grasses found in the Central Pampas of Argentina. We compared native wild grasses to maize starch grains, which can be distinguished from each other based on their size, shape and other attributes. The majority of the studied grains did not share morphological characteristics with maize starch grains. Considering this, it can be said that, if irregular and polyhedral grains with transverse or radial fissures dominate the starch assemblage, maize identification may be done on the basis of both morphology and size. Additionally, this research contributes to the characterization of the starch grains of the Panicoideae subfamily, which includes maize. Several classes of simple and compound starch grains are described and defined for native species of Pooideae, Chloridoideae, Arundinoideae, and Panicoideae subfamilies. The results obtained may constitute a baseline for the future determination of maize and wild grass use in archaeological contexts belonging to Middle/Late Holocene hunter–gatherers in the Pampas of Argentina and neighboring areas. 相似文献
100.
G. Huelga‐Suarez M. Moldovan M. Suárez Fernández M. Ángel de Blas Cortina J. I. García Alonso 《Archaeometry》2014,56(4):651-664
This paper continues the characterization of the lead isotopic fingerprint of ancient copper mines in the north‐west of Spain. In this work, the lead isotopic compositions found in copper ores from the La Profunda mine are presented. Azurites and malachites sampled from this deposit were subjected to lead isotope analysis by multicollector ICP–MS. The results showed a clear radiogenic lead signature compatible with the presence of uranium‐rich minerals (such as zeunerite) in the same mining complex. Moreover, a rare copper artefact, found in the galleries of the mine during its modern exploitation, was also analysed and showed that local mineral was used for its manufacturing. 相似文献