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1.
A method is described for the preparation of vertebral body and rib sections of archaeological context, for scanning electron microscopy (SEM). The specimens included in the present paper are macroscopically normal and are male and female in juvenile and adult age brackets. The changing directionality of trabeculae and the changing ratio of trabecular bone to cancellous space are noted in relation to the age at death.  相似文献   
2.
Several samples of pyramids from Giza were obtained. The samples were analysed by scanning electron microscopy, electron diffraction by X-rays, powder X-ray diffraction, inductively coupled plasmography, Fourier-transform infrared spectroscopy and other techniques. Some scientists who have recently studied the pyramids have suggested that the pyramids were poured into place, stone by stone. The prevailing theory among Egyptologists is, of course, that the pyramids were built from blocks of natural stone. All of the results obtained during this study directly support the concept that the pyramids are made of limestone and are not cementitious in nature.  相似文献   
3.
The paper reports the results of a research project aimed at the characterization of the floor bedding mortars of two Roman houses in Aquileia (north‐eastern Italy), the Domus delle Bestie Ferite and the Domus di Tito Macro. Seventy floor bedding mortars of the two domus were selected and almost half were fully minero‐petrographically characterized by means of optical microscopy operated in transmitted light (OM‐TL), X‐ray powder diffraction analyses coupled with quantitative phase analysis by means of the Rietveld method (XRPD‐QPA) and scanning electron microscopy with EDS microanalysis (SEM–EDS). The results indicate an evolution of the mortar preparation techniques over time in the mosaic of both houses. The materials are compared to the traditional Roman recipes for specific construction techniques.  相似文献   
4.
The handle‐shaped artefact is a special jade object of the Three Dynasties (c.2000–200 bc ) period. The manufacturing technology and function of the handle‐shaped artefacts are widely questioned. In this paper, two handle‐shaped artefacts from Yinxu (c.1300–1046 bc ) are tested by digital microscope, Raman spectrometer and scanning electron microscope. The results indicate that the handle‐shaped artefacts might be made in four steps, namely rough shape cutting, edge reforming, handle making and single‐side polishing. It also suggests that the handle‐shaped artefacts might be used as sacrificial offerings, but not as hairpins or handles.  相似文献   
5.
青铜箭镞是古代制造量最大、一次性使用的兵器,与要求甚高的青铜剑和青铜礼乐器等相比,在选材和表面处理等方面有很大的不同,其锈蚀过程最能反映材料在经过数千年后所产生变化。长江中下游地区环境潮湿,埋藏条件复杂,本研究利用扫描电子显微镜(SEM)、能谱仪(EDS)、X-射线衍射仪(XRD)、显微硬度等分析测试技术,从材料科学的角度对长江中游地区战国晚期古墓中出土的青铜箭镞的锈蚀现象和锈蚀机理进行了全面的研究和分析,以期为古代青铜器的保护提供更准确的信息和资料。结果表明,青铜箭镞的组织结构可分为完全矿化层、过渡层和心部原始材料等三个特征层,不同特征层具有不同的显微组织、化学成分、致密性,以及显微硬度等;并沿横截面观察和分析了锈蚀层中的微裂纹的性质和产生原因,即,平行于表面的裂纹是由矿化层氧化物膨胀引起的剥离开裂,其进一步发展将形成“粉状锈”,而垂直于表面呈放射状的裂纹是当圆柱形箭镞杆膨胀时,矿化层的塑性差,抗变形能力低而产生的开裂;锈蚀机理研究认为青铜器的锈蚀过程是环境中杂质元素通过过渡层沿界面能较高的α固溶体和(α+δ)共析体晶界或孔隙等缺陷逐步向内部扩散的结果。  相似文献   
6.
Changes in the stable carbon and nitrogen isotope ratios of modern bone samples heated to a variety of times and temperatures were used to determine the effect of heating on isotope ratios and the retention of organic matter in charred bones. For organic extracts produced by slow demineralization in weak acid, δ13C values were unchanged, while δ15N values increased by up to 5‰ and were primarily determined by heating temperature. Changes in the electron spin resonance (ESR) g-value of whole bone and organic extracts were also measured. For organic extracts from charred bones, the g-value was well-correlated with δ15N and temperature, suggesting that g-values could be used to estimate the charring temperature and original δ15N values of charred bones. Thus, g-values from demineralized extracts could be very useful in forensic investigations where it would important to reconstruct the thermal history of burned bones. Isotope ratios and g-values of demineralized extracts from four prehistoric components at three sites that produced cremated human bone were used to test whether the same approach can be applied to archaeological materials. While carbon isotope ratios of the prehistoric samples were similar to those of uncharred specimens, nitrogen isotope ratios were increased and the g-value corrections for nitrogen isotope ratios were not effective.  相似文献   
7.
This article presents and discusses the chronological layout of the final Mousterian and Uluzzian levels of Fumane Cave in northern Italy using 14C, ESR and TL methods. Given its complex sedimentary and cultural succession, Fumane is a key site to assess the Middle–Upper Palaeolithic transition in Southern Europe and to explore Neanderthal behaviour and to compare it with the first Aurignacians. Large ranges defined by the ESR and TL dates cover the radiocarbon ages for units from A11 to A4, respectively, from 42.8 to 32.5 ka BP become progressively younger in agreement with the stratigraphy, despite high dispersions within the same unit. Our estimates using chronometric data seem to support the hypothesis that the sequence may cover almost 10,000 radiocarbon yr and that from comparison with the sedimentological and palaeoecological data, the late Middle Palaeolithic and the early Upper Palaeolithic at Fumane occur in sediments formed under moderately cool to mild climatic conditions correlated to the Hengelo-Interstadial, shifting towards cooler and drier conditions. Finally, comparisons between the Fumane data set and other sites in the North-Adriatic region are discussed.  相似文献   
8.
Fifty‐seven glass samples from Carthage dating to the fourth to sixth century ad were analysed using the electron microprobe. The results show that these samples are all soda–lime–silica glass. Their MgO and K2O values, which are below 1.5%, suggest that they were made from natron, a flux that was widely used during the Roman period. The major and minor elements show that these samples can be divided into four groups, three of which correspond to the late Roman period glass groups that were found throughout the Roman Empire: Levantine I, and ‘weak’ and ‘strong’ HIMT. Of particular interest is our Group 2, which is technologically and compositionally similar to HIMT glass and the CaO and Al2O3 values of which are similar to those of Levantine I. Glass of similar composition has been reported by several authors and is predominantly found dating from the late fifth to seventh century. This could represent a ‘new’ glass group; therefore further study is needed to determine its origin. Also, this study suggests that the Vandal invasion in North Africa did not disrupt the glass trade between Carthage and the Levantine coast.  相似文献   
9.
The organization of ceramic production and distribution among the ancient Hohokam of the Phoenix basin, Arizona, has been documented in recent years with much detail. Based on diverse temper and clay compositions, the provenance of individual ceramics is routinely determined with considerable precision. One exception is phyllite-tempered pottery, which was made in one corner of the basin but also across a broad upland zone adjacent to the north. The phyllite-tempered pottery from different production sources cannot be distinguished on the basis of their temper type. As shown with assays with an electron microprobe, however, both the temper and clay fractions are chemically diverse and geographically distinct, allowing many of the phyllite-tempered wares to be sourced. Among the phyllite-tempered ceramics consumed in the Phoenix basin, some are shown to have been made locally, but, surprisingly, large numbers were imported from the northern uplands. Their numbers support the idea that the connection between the Phoenix basin and the northern uplands was a prominent component of the Hohokam regional economy despite the great difference between them in settlement size and density.  相似文献   
10.
From a 1000-year-old mummy, found unwrapped in the sand of the desert at Chiribaya Alta in Southern Peru, two different kinds of tattoos were investigated: decorative tattoos displaying different animals and symbolic ciphers were present on the extremities and tattooed circles on the neck region.  相似文献   
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