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41.
五千年前陶质建材的测试研究   总被引:1,自引:0,他引:1  
迄今为止的考古发掘表明,我国最早的陶质建材,应该是距今5500年左右的凌家滩“红陶块”。考古学家推测其原料为粘土矿物,烧成温度约800~1000℃,且其物理性能与砖质建材较为接近,应为“砖的雏形”,为此,本工作测试分析了凌家滩“红陶块”的物相组成、烧成温度、吸水率与抗压强度,同时对比分析了明砖、汉砖、现代砖的物理性能,发现“红陶块”系粘土原料在950℃以上温度烧制而成,其吸水率和抗压强度由外向内呈梯度变化,内层的抗压强度、吸水率接近于现代砖和汉砖,业已超过明砖样品,所有这些分析结果,皆支持考古学家关于凌家滩“红陶块”为砖的雏型的推测。  相似文献   
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This paper presents a revised version of the Coimbra method for recording fibrocartilaginous entheses. The method itself is the only biologically appropriate recording method for fibrocartilaginous entheses that scores features separately, thereby ensuring that the aetiology of individual features can be studied. The method divides the enthesis into two zones, scoring the relevant features in each zone. These features represent either bone formation or bone destruction and include erosive lesions, fine and macro‐porosity, and cavitations. The revised method includes a new feature, textural change, which is scored as absent or present when it involves 50% or more of the surface. All other features are now scored as zero (absent), one or two with the higher score representing greater expression of the feature. This change in scoring has led to the reduction of inter‐observer error with approximately 80% agreement for overall feature scores for both the common extensor origin and subscapularis insertion. The simplification of the scores and the reduction in inter‐observer error mean that the method is now recommended for widespread use. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
44.
A mass of Longquan porcelain shards carved with ‘Guan’ or the dragon patterns were unearthed in the early Ming Dynasty layer of the Fengdongyan kiln site at Dayao County. These celadon shards were fired in the Hongwu and Yongle eras of the Ming Dynasty. In order to research the raw materials and firing technology of the imperial porcelain, 85 typical shards were analysed by energy‐dispersive X‐ray fluorescence (EDXRF). The results indicate that the contents of TiO2 and Fe2O3 in the body vary in the Hongwu and Yongle eras. Compared with Longquan glazes in the Southern Song Dynasty, the average values of K2O, Fe2O3 and TiO2 are higher, but that of CaO is lower in early Ming imperial porcelain glazes. Principal components analysis (PCA) shows that different degrees of elutriation of the same raw materials are the main reason for this difference in the Hongwu and Yongle periods. However, the raw materials of imperial porcelain glazes show no obvious changes and have inherited the earlier tradition. The production and firing technology of imperial porcelain reached a higher level and had not declined in the Early Ming Dynasty.  相似文献   
45.
为了解河南鹿邑太清宫长子口墓出土的部分典型玉器的材料属性与制作工艺,用多种无损科技分析技术对其进行了现场分析,获取了玉器材质矿物组成、纹饰微观形貌、穿孔孔径及内部微痕特征、表面琢磨微痕等综合物理化学信息。基于科技分析结果,确定了玉器的材质属性以及玉器表面纹饰、钻孔、琢磨等制作工艺相关信息。结合考古学背景资料信息,探讨了长子口墓地出土玉器在材质、器形、功能与工艺之间存在的关系。  相似文献   
46.
城市公共空间的意义与秩序,建构于使用者利用空间并遇到相关主体的日常场景中。论文以空间实践为理论视角,搭建涵盖身份、流动、权力的分析框架,发掘开封小吃夜市摊贩的身份属性与流动特征,探寻边界和节奏同权力运作的关联。研究认为:①回族摊贩为夜市赋予民族特性和地方性特色,回族社区是塑造从业身份的引力场;②摊贩通过短距离流动将集体社会文化属性嵌入空间,造就夜市和清真寺的空间邻近关系;③夜市的正规性附着于空间边界,场所的可占据性呈现于时间节奏,反映出权力运作依赖于空间资源的有限性与区位条件的差异性。空间实践能够为解释空间变迁中意义与秩序的形成逻辑提供理论框架,此案例分析可为公共空间的长效治理提供政策启迪。  相似文献   
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The Tequila Valleys, in Jalisco, Mexico, are well-known in archaeology for an early complex society known as the Teuchitlán tradition (350 b.c.a.d. 450/500), but later developments have received little attention. Here I report on the first systematic, full-coverage survey of the Tequila region north of the Tequila volcano. I explore the ways in which the societies that occupied this territory experienced sociopolitical change diachronically by investigating settlement scale, integration, complexity, and boundedness. Through the use of these core features, I analyze how each changed in varying ways, resulting in patterns that do not conform to static societal categories. Interestingly, there is no evidence that a large polity controlled the entire region at any point in the sequence. Results indicate a dynamic sociopolitical landscape that did not develop along any predetermined pathway.  相似文献   
49.
The Lv family tombs in Lantian, Shaanxi Province are one of the most important archaeological sites of China in recent years, providing numerous objects and a wealth of information for the study of the history of the Northern Song dynasty. There were a large number of exquisite cultural relics unearthed from the tombs, including one porcelain box containing white powder, which was identified as women's makeup. The phase composition, microstructure, thermal properties and characteristics of the trace elements in the unearthed white cosmetic powder were comprehensively analysed by X‐ray diffraction (XRD), scanning electron microscopy (SEM), differential scanning calorimetry – thermogravimetry (DSC–TG), Fourier transform infrared (FT–IR) microscopy and inductively coupled plasma atomic emission spectroscopy (ICP–AES). The white makeup powder was determined to be a product made from high‐quality freshwater pearls. These results, for the first time, showed evidence that freshwater pearl powder was used as a cosmetic in ancient China using archaeological objects, providing scientific evidence and new clues to enrich and expand research into the ancient Chinese cosmetic materials.  相似文献   
50.
X. Zhou  T. J. Burbey 《Geofluids》2014,14(2):174-188
The initiation of hydraulic fractures during fluid injection in deep formations can be either engineered or induced unintentionally. Upon injection of CO2, the pore fluids in deep formations can be changed from oil/saline water to CO2 or CO2 dominated. The type of fluid is important not only because the fluid must fracture the rock, but also because rocks saturated with different pore fluids behave differently. We investigated the influence of fluid properties on fracture propagation behavior by using the cohesive zone model in conjunction with a poroelasticity model. Simulation results indicate that the pore pressure fields are very different for different pore fluids even when the initial field conditions and injection schemes (rate and time) are kept the same. Low viscosity fluids with properties of supercritical CO2 will create relatively thin and much shorter fractures in comparison with fluids exhibiting properties of water under similar injection schemes. Two significant times are recognized during fracture propagation: the time at which a crack ceases opening and the later time point at which a crack ceases propagating. These times are very different for different fluids. Both fluid compressibility and viscosity influence fracture propagation, with viscosity being the more important property. Viscosity can greatly affect hydraulic conductivity and the leak‐off coefficient. This analysis assumes the in‐situ pore fluid and injected fluid are the same and the pore space is 100% saturated by that fluid at the beginning of the simulation.  相似文献   
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