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191.
Site F2 in the Timna Valley, Israel, is a small copper smelting site of ‘primitive’ technology, dated by its excavator to the Pottery Neolithic (sixth to fifth millennium bce ). This early date challenges the common view of the beginning of smelting technology in the Levant and has been contested by various scholars since its publication. In this study, we present results of archaeointensity experiments conducted on slag fragments from the site. The slag yielded an excellent ancient geomagnetic value (64.1 ± 1.1 μT) that, when compared to the Levantine master curve, suggests an age not older than the second millennium and most probably between the 13th and 11th centuries bce . In addition to demonstrating the applicability of geomagnetic archaeointensity experiments to independent dating of slag, we discuss the implications of the current results for the socio‐historical picture of the Timna Valley, and in particular for the way in which technological developments were previously modelled in the archaeometallurgical research on the region.  相似文献   
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Spiritual equality, responsibility, and accountability for both men and women are well‐developed themes in the Qur'an. Spiritual equality between men and women in the sight of God is not limited purely to religious issues, but is the basis for equality in all aspects of human endeavor. This article's main interest is in the woman's status, and her role within the Arab countries. Islam is the main religion—its principles, values, and practices are dominant in the region. Therefore, this article introduces and discusses the misinterpretation of women in Islam, with special consideration of Muslim women's rights and their roles within the Muslim society. This will help to enhance future discussions of social behavior, values, and attitudes toward women in Islam. In the last few decades there has been a great misunderstanding in many aspects of public consciousness about the role of women in Arabic society. There is a significant gap between the status of males and females. However, this gap is more evident in rural areas. The level of women's rights and roles in many Arabic countries prevents women from improving their economic growth and development. This gender gap is the result of social, religious, cultural, and gender inequality. More specifically, it results from structural constraints faced by women. Gender inequality is not a new issue, nor is it only Muslim women who are suffering from this inequality. There is gender discrimination almost everywhere. The Qur'an is the basis of Islam, and encompasses rules, legislation, examples, advice, history, and system of the universe. It draws a picture of the earth and describes the roles of human beings. The Qur'an is the answer to the spiritual and material needs of the Islamic society, and is an exposition and an explanation of all aspects of life.  相似文献   
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Fifteen desalinated sandstone drill core samples from Umm Ishrin Sandstone Formation in Petra (Cambrian age) were used for this study. The samples were mineralogically analysed using X‐ray diffraction and their physical properties were also determined. Samples with similar physical properties and mineralogical composition were taken for further experimental work. After desalination, thermal and hydric dilatation coefficients were measured, then three types of salts (NaCl, KCl and Na2SO4·10H2O), which have high solubility and consequently are the most dangerous to building stone (and are also detected in the sandstone monuments in Petra), were introduced into the samples and their contents were calculated. The results show that salt crystallization in the pores of building stones can increase their thermal dilatation and decrease their hydric dilatation to varying extents, depending on the nature of the salt. The average increase in the thermal dilatation coefficient per unit mass of salt is the lowest for the Na2SO4·10H2O‐salted samples with a value of 5.3%, while the NaCl‐salted samples have the highest value with 7.8% per salt mass. The average percentage of the decrease of the hydric dilatation coefficient is 1061% for Na2SO4·10H2O‐salted samples per mass of salt content; the NaCl‐salted samples have a value of 1510% per mass of salt content, and the KCl‐salted samples almost the same value. For the salt‐free samples, it was found that in climatic conditions with a high temperature range, the deterioration of sandstone due to temperature fluctuation is more effective than that caused by change in the moisture content, while samples with high salt content suffer more from hydric dilatation.  相似文献   
196.
Palygorskite is a rare clay mineral used by the ancient Mayas for fabricating the Maya blue pigment and for other purposes. It seems to have been obtained from a restricted area in the Yucatán peninsula where important archaeological sites are found. Geological samples from different localities in this area show a high content in palygorskite, indicating that this clay is widespread in Yucatán. Combining structural, morphological, compositional and geochemical methods, we analysed the common characteristics of Yucatecan palygorskites, and compared them with palygorskites from other origins around the world. These results can be used for defining a fingerprint of Yucatecan palygorskite to be used in provenance studies of archaeological artefacts, in particular the Maya blue pigment.  相似文献   
197.
The pigments, binders and execution techniques used by the Nasrids (1238–1492) to polychrome carpentry in the Hall of the Mexuar Palace at the Alhambra (Granada, Spain) were studied using optical microscopy, scanning electron microscopy with EDX analysis, selective staining techniques and gas chromatography – mass spectrometry. This pioneering investigation presents the first results of a research project devoted to filling gaps in the knowledge of Nasrid art, traditionally approached by stylistic studies. Moreover, it is essential for the polychromy conservation of the studied artworks, and will help to clarify historical and painting uncertainties in the Alhambra monument. The palette consists of a limited range of colours: white (lead‐base pigment), red (cinnabar and red lead), blue (lapis lazuli), black (carbon‐based) and false gold (golden tin). Tempera grassa was the painting technique identified. Two types of grounds were used: (i) gypsum in calligraphy decoration for the false gold technique, and (ii) synthetic minium in geometric drawings in carpentry. Organic insulating layers of linseed oil were used between paint strata. Artists applied synthetic minium to protect the wood (Juglans regia and conifer) against attack by xylophages. To lighten the surface darkened by this ground layer, powdered tin was added to achieve a metallic lustre.  相似文献   
198.
This project follows on from an initial study of Celtic gold coins from the Middle Rhine/Moselle region, which was based on material found at the Martberg, a Late Iron Age/Roman sanctuary and settlement (River Moselle, western Germany; Bendall 2003 ). The earlier work was expanded to encompass over 100 examples of various other regional Celtic gold coinages from the collection of the Römisch‐Germanisches Zentralmuseum, Mainz. The alloy (Au–Ag–Cu) and trace element compositions (in particular Ni, Sb and Pt) were determined by EPMA and LA–ICP–MS, respectively, and their Pb isotope signatures were measured by LA–MC–ICP–MS. Of the 28 trace elements measured, only Ni, Sb and Pt were found to show meaningful variations and so only they are presented here. In particular, differences in the Pt/Au ratios between various groups of earlier coinage (imitations of Philippus and Alexander/Nike staters, Sch. 23 and some early Boian coins) on the one hand, and the majority of the Boian and the southern rainbow cup coinages on the other, indicate a significant difference in the gold sources exploited for these regional coinages. The Pb isotope data confirm previous conclusions that the contribution of gold to the total lead in the Au–Ag–Cu coin alloys can be detected, especially for coins with over 70% gold, and show that possible gold sources include both eastern Mediterranean and Alpine sources. Combining the Pb isotope data with the Pt/Au ratios allows the potential gold sources to be further differentiated.  相似文献   
199.
Osteoporosis is a condition of reduced total bone mass per unit volume for the normal ratio of bone mineral to bone matrix. The present work deals with the investigation and evaluation of osteoporosis in ancient Egyptians of two social classes from the Old Kingdom in Giza. The aims of this study are to provide information about the lifestyle and health status of ancient Egyptians, and to detect the causes of osteoporosis. The material consisted of 74 skeletons (43 males and 31 females) from two different social classes (high officials and workers). Skeletons were excavated from the Giza Necropolis and belonged to the Old Kingdom (2687–2191 BC). Dual energy X‐ray absorptiometry (DEXA) was used to measure bone mineral density (BMD) at different skeletal sites (radius, fourth lumbar vertebra and head of femur). Moreover, scanning electron microscopy (SEM) was used to show the microarchitectural structure of the bone. Results showed a significant decrease of BMD values in old age groups compared with younger ones in both sexes. In addition, SEM of trabecular bone in osteoporotic cases demonstrated that the horizontal trabeculae were more affected than the vertical trabeculae. Comparison between high officials and workers revealed that osteoporosis was more frequent in male workers than in male high officials, and in female high officials than in female workers. An elevated prevalence of osteoporosis among male workers may be related to the effects of nutritional stress and excessive workload, while a sedentary lifestyle may have played a role in the occurrence of osteoporosis among female high officials. Moreover, osteoporosis occurs earlier and more frequently in females than males, which may be related to the hormonal changes that accompany the menopause in females. This study emphasises the importance of gender and lifestyle factors in influencing the severity of osteoporosis. Age‐related bone loss at most skeletal sites is noted in both sexes of ancient Egyptians. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
200.
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