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101.
102.
吴静霞 《文物保护与考古科学》2008,20(4):55-58
考古出土实物研究表明,商周青铜器铭文制作,通常是先雕刻正阴字铭文模,然后翻制反阳字铭文活块泥芯,镶嵌于主体泥芯合适位置组成复合泥芯,最后在浇铸青铜器时一并铸成于器物内壁上。复制具有151字铭文的西周晚期青铜颂鼎,整体采用失蜡铸造工艺,铭文制作借鉴商周青铜器陶范铸造的相关工艺,多次翻制制作一块铭文蜡片,嵌入模具型腔后翻制整体硅橡胶泥芯,获得了理想的效果。 相似文献
103.
为了筛选出能用于丝织品文物防霉且对人、环境安全的生物代谢产物,选用目前在国际上得到广泛认可的安全性防霉剂纳他霉素,在一定的光照条件下,采用抑菌圈法对现代天然丝织品材料进行了防霉试验。结果表明,无论是否以乳酸链球菌素作为助剂,500μg/g(以有效成分计)纳他霉素在丝织品上防黑曲霉、青霉、毛霉效果明显。纳他霉素对白色丝织品的色泽和机械强度无破坏性影响。纳他霉素在丝织品文物防霉上有应用前景。 相似文献
104.
为研究细菌纤维素对木质文物的修复效果,首先检测了产纤维素的醋杆菌Acetobactersp.PDA静置培养时的生长,然后将其与小块的饱水木材一起静置培养,通过测定木块处理前后的湿重及扫描电镜观察,结果显示细菌纤维素对木质文物有一定的修复作用。 相似文献
105.
长江中游地区楚墓中出土的青铜箭镞的锈蚀现象及锈蚀机理研究 总被引:1,自引:0,他引:1
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
106.
Josep Antoni Alcover 《Journal of World Prehistory》2008,21(1):19-84
The paper aims to elucidate the first human colonization of the western Mediterranean island of Mallorca by answering such questions as: What was the cultural identity of the first archaeologically identifiable human settlers? What was the chronology of colonization? Where did the colonizers originate? And what were their contacts during the initial phase of settlement? It is based on recently acquired chronological data and on a review of the classical sources. A precise chronology for the first colonization event is proposed, supporting the idea that human settlement on Mallorca started within the period 2350–2150 cal BC. The coast of Languedoc, between the rivers Vidourle and Rhône, is the most probable source region. Whether the first settlers were derived from an Early Bronze Age or a Late Copper Age mainland culture remains unresolved. A rapid initial population growth following initial colonization is proposed. The available evidence points to the development of an essentially isolated population on Mallorca, developing an autochthonous culture with only limited contacts to mainland regions. 相似文献
107.
Robert J. Blumenschine Fidelis T. Masao Joanne C. Tactikos James I. Ebert 《Journal of archaeological science》2008
Ongoing excavations at Olduvai Gorge, Tanzania, reveal tremendous variability among stone artifact assemblages across the Plio-Pleistocene Olduvai Lake Basin during Bed I and lower Bed II times. Theoretically, stone artifact traces of Oldowan hominin land use are determined by the distribution of larger mammal carcasses and arboreal refuge from predation as well as proximity to stone material sources. 相似文献
108.
P.G. Whitehead S.J. Smith A.J. Wade S.J. Mithen B.L. Finlayson B. Sellwood P.J. Valdes 《Journal of archaeological science》2008
An annual water balance model for Wadi Rajil, in Northern Jordan, is used to simulate the ancient water supply system for the Early Bronze Age site of Jawa. The model includes: water delivery from the catchment; local pond storage; and water demand for people, animals and irrigation. A Monte Carlo approach is used to incorporate the uncertainty associated with a range of factors including rainfall, evaporation, water losses and use. The stochastic simulation provides estimates of potential population levels sustainable by the water supply system. Historical precipitation estimates from a Global Circulation Model, with uncertainty bounds, are used to reconstruct the climate at Jawa in the Early Bronze Age (EBA). Model results indicate that the population levels in the predicted wetter conditions during parts of the EBA could have risen to ∼6000 and may have been higher in wet years. However, palaeoclimatic proxies also suggest prolonged droughts in the EBA; and during these periods the water management system was unable to provide adequate supply for a population of 6000. The utility of Monte Carlo based hydrological modelling as a tool within archaeological science is discussed. 相似文献
109.
Elimination of extraneous DNA in fossil specimens is of paramount importance for the successful isolation and analysis of authentic DNA; this is especially true when the specimens are of human origin. Bones and teeth are commonly decontaminated with bleach containing the powerful oxidising hypochlorite ion. The procedures involve either submersion in or wiping with the chlorine agent. Using the radioactive isotope Cl36 we showed that submersion of fossil teeth in solutions of small ions such as Cl− or hypochlorite, ClO−, cause that they migrate right into the pulp. This may lead to the unwanted destruction of authentic DNA. However, using pairs of teeth from the remains of four ancient Europeans (1000–2000 YBP) as well as tooth and hair from an Inuit skull (>300 YBP) we provide evidence that at least some endogenous human fossil DNA survives in powdered pulp/dentin that has been submersed in 2% hypochlorite. Further, we show that powdered pulp/dentin deliberately contaminated with huge amounts of a 414 bp PCR product is effectively decontaminated by suspension in 2% hypochlorite for 5 min. Decontamination of fossil material from teeth may therefore be accomplished by a short direct action of hypochlorite on the powdered specimen rather than less controllable and less efficient external treatments of the whole specimen. 相似文献
110.
It is of vital importance to be able to sex identify cattle remains to understand the strategies and importance of cattle husbandry in an ancient society. This is usually done from osteoarchaeological assemblages and often relies on measurements of metapodials. The breadth measurement of the distal trochlea is considered an easy way to identify the sex. Bones from males appears to be easily distinguishable from female counterparts, although it has been complicated to find an external control for the morphological results. Here we investigate the reliability of these particular morphometrics for sex identifying cattle bones with molecular genetics. We use a sex discriminating single nucleotide polymorphism in the ZFXY gene and we apply it to DNA from the bones. To keep the fragment size short and suitable for ancient DNA we base the test on a SNP. The test confirms the osteological sex identification in all cases were DNA could be retrieved. This molecular method can also be used when no fragments suitable for osteological sex identification can be found or when the measurements are non-conclusive. 相似文献