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1.
Cobalt-blue colorant was first used in the 18th Dynasty in the New Kingdom of Egypt. The source of this cobalt was cobaltiferous alum from the Western Oases of Egypt. The use of this alum, especially in glass, was suddenly limited at the end of the 18th Dynasty. There is little evidence of the production of cobalt-blue glass in the Ramesside Period (the 19th–20th Dynasties) in the New Kingdom of Egypt. In this study, we brought a portable X-ray fluorescence spectrometer to two archaeological sites located in the Memphite region and used it for onsite analyses of Ramesside cobalt blue-colored glasses and faiences. This method revealed that the compositional characteristics of the cobalt-blue colorant in these Ramesside glasses and faiences is different from the colorant derived from cobaltiferous alum used in the 18th Dynasty, based on the comparison of transition metal composition and alumina content with those of the cobalt blue-colored artifacts from the 18th Dynasty. This result suggests that a new cobalt source other than cobaltiferous alum from the Western Oases was utilized in Egypt during the Ramesside Period.  相似文献   
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This article presents a bi‐objective model for determining the number and size of finite size facilities. The objectives are to minimize both the average closest distance to facilities and the probability that a random line intersects facilities. The former represents the accessibility of customers, whereas the latter represents the interference to travelers. The average closest distance and the probability of intersecting facilities are derived for circular facilities randomly distributed in a circular city. The analytical expressions for the average closest distance and the probability of intersecting facilities demonstrate how the number and size of facilities affect the accessibility of customers and the interference to travelers. The model focuses on the tradeoff between the accessibility and interference, and the tradeoff curve provides planners with alternatives for the number and size of facilities.  相似文献   
3.
The provenance of Early Bronze Age and early Middle Bronze Age pottery produced between 2100 and 1970 B.C. and excavated from Kaman-Kalehöyük, Turkey was studied using mineralogical methods, including heavy mineral analysis and geochemical study of individual hornblende grains. The relative abundances of heavy minerals in the fabrics of 20 Early Bronze Age (EBA) and early Middle Bronze Age (MBA) pottery sherds, together with 27 local sediments collected within a radius of 25 km of the site were studied. The heavy mineral distributions in the Kaman region were statistically analyzed for consistencies in their occurrence. Amphibole was found to be the most abundant heavy mineral in most of the analyzed samples, followed by titanite and epidote. The amounts of other minerals such as garnet, clinopyroxene, and zircon are subordinate. Different proportions of heavy minerals in the fabrics allow categorization of the EBA and early MBA potteries into 5 groups. Comparative study of heavy mineral assemblages of local sediments and pottery suggests that half of the EBA and most of the MBA potteries were produced from sediment near the excavation site, whereas the other half of the EBA potteries were produced from sediment occurring at 25 km east or more east of the site. The geochemistry of individual amphibole grains was studied by electron-microprobe analysis. Most of the studied amphibole grains are calcic and aluminous, corresponding to hornblende. They can be further characterized into four types based on their chemical composition. The combination of heavy mineral identity and hornblende geochemistry provides diagnostic evidence for the origins of Kaman-Kalehöyük pottery. These and analogous heavy mineral techniques are effective archaeometric tools for determining pottery provenance.  相似文献   
4.
The variation of electron spin resonance (ESR) signal intensities and thermoluminescence colour images (TLCIs) of quartz was investigated in the present study for various rocks and sediments in Japan, to discuss the possibilities of identifying the sediment provenance. The ESR signal intensity of the E1’ centre in the same grain size in granitic quartz varies from sample to sample, except for that in Quaternary samples of volcanic sediment, which is very low, close to the noise level. It was found that the diagram, ESR intensities of Al versus Ti-Li centre signal intensities, distinguish volcanic from the same grain size in granitic quartz as well as distinguish individual tephra from another. The TLCIs from volcanic quartz and some granitic quartz samples is almost red and that from the rest of granitic and metamudstone quartz is blue as results of TLCIs although the emission intensities are different. Our results suggest that examining the multiple-centre signal intensities of ESR and the TLCIs are effective to identify the source of quartz and to estimate the sediment provenance.  相似文献   
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Rheumatological diseases, whether inflammatory or degenerative, are ubiquitous among modern Asian people but very few palaeopathological studies have been performed in Asia on this subject. Since 1996, we have been carrying out a palaeoepidemiological survey of rheumatic diseases in ancient Chinese and Japanese skeletal populations. Findings on the spinal column in ancient Chinese populations (ca. 5000 bc –ad 1644) in Henan Province (centre of the Yellow River Civilization) are reported in this study. The examined number of the people over 20 years old was 365 (185 males, 169 females and 11 unsexed). Of these, 248 were young adults, 98 were middle adults and 19 were old adults. Crude prevalence (number/100) in total population of vertebral osteophytosis/facet osteoarthritis was 17.5/7.7, 17/3.7 and 44.6/21.1 at the cervical, thoracic and lumbar spine, respectively. That of ossified anterior longitudinal ligament (OALL) or Forestier's disease was around 3 at each of the cervical, thoracic and lumbar spine. Ossification of the posterior longitudinal ligament (OPLL) of the cervical spine was observed in five out of 114 skeletons with cervical spine preserved, while it did not exist in any thoracic and lumbar segment. Ossification of the ligamentum flavum (OLF) was predominantly observed in the thoracic spine, the crude prevalence of which was 36.7. Overall spinal degenerative lesions seemed to have been more prevalent and spinal ligament ossifications less prevalent in ancient Chinese populations than in modern people. None of the inflammatory lesions like rheumatoid spondylitis, as well as seronegative spondyloarthropathies, were detected. This is the first palaeopathological study in which the prevalence of OPLL and OLF, the two clinically important spinal ligamentous ossifications causing myelopathy in modern mankind, was surveyed in ancient skeletons. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
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This study focuses on the chemical composition of Islamic plant-ash glass (dated from the 9th to 11th centuries) excavated from the Raya/al-Tur area on the South Sinai in Egypt. Plant-ash glass objects from the Raya site were classified into three compositional types based on on-site chemical analyses with a portable X-ray fluorescence spectrometer. Based on typological characteristics and chemical composition comparisons with contemporary glass objects from other Islamic sites, one hypothesis holds that plant-ash glass objects produced in the Syria–Palestine or Mesopotamian regions could have been imported to Raya during the 9th to 10th centuries. In particular, some colorless glass vessels with a high magnesium/calcium ratio were noted to exhibit post-Sassanian cut decorations. Conversely, most of the bluish-green plant-ash glass objects from the Monastery of Wadi al-Tur near the Raya site exhibited relatively high levels of aluminum, titanium, iron, and lead. These pieces were likely produced during the Fatimid period (late 10th to 12th centuries), and based on their elemental composition, possibly originated in Egypt. The present work provides a greater understanding of chronological changes in post-9th century Islamic plant-ash glasses and the development of social and commercial networks within the Middle Eastern area.  相似文献   
9.
This article examines the k th nearest neighbor distance for three regular point patterns: square, triangular, and hexagonal lattices. The probability density functions of the k th nearest distance and the average k th nearest distances are theoretically derived for k =1, 2, …, 7. As an application of the k th nearest distance, we consider a facility location problem with closing of facilities. The problem is to find the optimal regular pattern that minimizes the average distance to the nearest open facility. Assuming that facilities are closed independently and at random, we show that the triangular lattice is optimal if at least 68% of facilities are open by comparing the upper and lower bounds of the average distances.  相似文献   
10.
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