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1.
The bodies and glazes of 27 early Western Zhou proto‐porcelain samples from Yejiashan cemetery, Hubei Province, were analysed using LA‐ICP–AES, SEM, XRD, a thermal expansion instrument and other analytical methods. The results indicated that the bodies of all samples were characterized by high silicon and low aluminium, and were made with porcelain stone raw materials found in the south of China. The glazes are typical of high‐temperature calcium glazes of the CaO (MgO) – K2O (Na2O) – Al2O3 – SiO2 series, with relatively high Mn and P content, which was probably caused by the addition of plant ashes. The physical properties and phase compositions of Yejiashan proto‐porcelain show that firing processes were still in the early stages of development in ancient China. Multivariate statistical analyses indicated that Yejiashan proto‐porcelain might have come from the Deqing area, in Zhejiang Province. These results provide new archaeological evidence for research on issues related to material flow in the Western Zhou dynasty.  相似文献   
2.
A quantitative bioenvironmental study of cranioskeletal size has been made of a latitude-ordered sequence of 14 series of adult skeleton sets (N=305): the archaeological remains of aboriginal maritime peoples inhabiting the west coast of North America between southern California and the Arctic. Of eight osteometric parameters of cranioskeletal size developed, the most important are partial skeleton volume (PSK) and cranial capacity (CC); and the principal bone-affecting environmental factors are the northerly climate (CLIM2c), the reconstructed diet deficient in calcium and overabundant in animal foods and vitamin D (DIET3c), and demographic stress (DSg). Prior research has demonstrated that cranioskeletal size increases with geographical latitude and decreases under dietary calcioprivation and unphysiologically high birth rates. Upon linear multifactorial statistical analysis our main finding, limited to the Amerindian subsequence (n=11 series) from the Santa Barbara Channel, the San Francisco Bay Region and the Northwest Coast, is that PSK and CC vary in direct proportion to CLIM2c, and inversely with DIET3c and DSg. Controlling for the latter two osteoantitrophic factors, coastal Amerindian female PSK rises by 9% between 34 and 54°N latitude, CC by 5%; and the male incremental rates are somewhat higher, 13 and 10%, respectively. This newly discovered climate-dependent race cline, an example of Bergmann's Rule, is interpreted as factual evidence of a mid-Wisconsin or earlier arrival date for the first Palaeoindians. Cranioskeletal size of the very small (n=3 series) Western Eskimo subsequence approximates the northernmost values of the coastal Amerindian distribution. © 1998 John Wiley & Sons, Ltd.  相似文献   
3.
Optical Coherence Tomography (OCT) is a non-invasive subsurface 3D imaging technique based on the Michelson interferometer. The non-invasive nature of OCT and its speed of acquisition makes it possible to image large volumes of intact objects to yield a complete overview of the microstructure. The production methods for ancient Egyptian faience were first investigated using scanning electron microscopy (SEM) imaging of the microstructure in polished sections and microprobe analysis of the composition of the glass phases. These studies were based on original Egyptian faience objects and laboratory reproductions of faience beads made using three different production methods. The microstructure of the same laboratory samples and the Egyptian faience objects from the British Museum Research Laboratory Collection are re-examined using OCT. It is found that OCT virtual cross-section images can be used to group ancient faience objects into three categories on the basis of the morphology of the surface glaze layer and the glaze/core interaction layer. The OCT images correspond well with SEM images of polished sections of ancient faience objects and laboratory reproductions. The virtual cross-sections produced by OCT are somewhat limited by the penetration depth, which is affected by the high absorption coefficient of the material and, therefore, cannot always provide information on the presence or absence of interparticle glass that binds together the quartz particles in the core. Nevertheless, the top two layers are well imaged and since OCT images can be obtained rapidly and without the necessity of removing a sample, the method can be applied to a very much wider range of ancient faience objects than is possible by SEM examination of polished cross-sections. In summary, this paper examines to what extent OCT can assist the investigation of the production techniques of ancient Egyptian faience.  相似文献   
4.
The effect of carbonic anhydrase enzyme on the precipitation kinetics and phase transformations of calcium carbonate, and on the strength development of lime mortars has been investigated with saturated lime solutions, lime pastes and lime mortars under atmospheric conditions. The results clearly show that carbonic anhydrase catalyzes the reaction between carbon dioxide and aqueous lime, and increases the rate of calcium carbonate crystallization, the yield of the carbonation reaction and mortar strength at early ages. This is most likely a kinetic effect associated with the increased rate of carbonate ions supply to the solution by the enzyme. In addition, this enzyme favors the formation of stable calcite and significantly modifies its morphology by developing new crystal faces. These results suggest a novel approach for accelerating the hardening of lime mortars using carbonic anhydrase enzyme, which may offer a potentially novel approach with significant benefits on the applications of lime mortars in architectural heritage conservation as well as in construction.  相似文献   
5.
Quantitative calculations on the use of natural resources provide valuable tools, which can give new insights to old questions and rise new ones. In this article, I compare the wood consumption in the production of potash, saltpeter and pine wood tar in 19th century Finland. My calculations shows that in the 19th century the cumulative wood consumption in the production of potash might have been higher or at least on the same level as in the production of tar, while the production of saltpeter consumed only a fraction. In the 1830s their combined wood consumption reached the level of slash‐and‐burn cultivation.  相似文献   
6.
中国传统灰土灰浆强度增强方法研究   总被引:4,自引:0,他引:4  
中国传统灰土灰浆中水硬性凝胶材料-水合硅酸钙和水合硅酸铝的形成可以大幅度提高其强度,但在自然条件下生成此类水硬性化合物需要很长时间。本文借鉴现代水泥工艺中利用焙烧黏土材料可提高火山灰活性的原理,从而有效缩短形成水硬性化合物的反应时间,在短时间内大大提高灰浆的强度。以此为出发点,加工制备性能优良的灰浆材料,为传统砌体建筑的保护提供适宜的保护修复材料。  相似文献   
7.
This study deals with the mineralogical and chemical characterization of archaeometallurgical material from the Roman archaeological site of Castra (Ajdov??ina, western Slovenia). Samples were initially analysed via optical microscopy and X‐ray powder diffraction, with the composition of individual phases then determined using scanning electron microscopy coupled with electron‐dispersive spectroscopy, and Raman microspectroscopy. Chemical investigation was carried out by using inductively coupled plasma atomic emission spectroscopy to measure the major element content. The results showed that the slag originated from iron smithing operations, with calcium‐rich olivines, as well as wuestite and leucite, the most abundant phases. The investigated slags were also found to be characterized by significantly high lime levels, which probably promoted the formation of the calcium‐rich olivines.  相似文献   
8.
An osteometric–statistical study of residual rickets (RR) skeletal plasticity has been made of a time-ordered sequence of 11 series of adult skeleton sets (n=251) from shellmound sites around San Francisco Bay (the Bay) spanning the three archaeological horizons of Central California Indian prehistory in this region: Early (EH), Middle (MH) and Late (LH). To control for major differences of subsistence ecology and ethnolinguistic affiliation, the Bay sequence was further subdivided into four subregions: East (EB, Costanoan), South (SB, Costanoan, high acorns), West (WB, Costanoan, low acorns) and Northwest (NWB, Coast Miwok). In the eight EB series, a non-linear downward trend in cranioskeletal size was observed between EH and LH2, coinciding with a modest upward trend in the RR-15B score. To ascertain if food calcium deficit (CADEF) can explain the observed secular decline in cranioskeletal size, the evolving aboriginal Bay archaeodiet—relatively high in marine mammals, birds, fish and calcium-rich mollusks—was reconstructed by the diet grid method: in the three subregions with large stands of oaks (EB, SB, NWB), CADEF rose from negligible in the EH to moderate in the LH, as the subsistence base became more dependent on leached acorn meal for energy. Temporal and areal variation in Bay cranioskeletal size relates mostly to CADEF, demographic stress in females (DS), and the ‘male nutritional advantage interaction co-factor’ (MNAIC), in descending order of importance. This study has also confirmed the existence of the San Francisco Bay Indian physical type.  相似文献   
9.
We conducted an identification of a substance isolated from a T‐shaped ornamental element excavated from a Globular Amphora Culture tomb at the Kowal 14 archaeological site in Poland. 14C dating indicated 4105 ± 35 bp (POZ‐21912) and 3990 ± 50 bp (POZ‐21910). Analytical methods such as SEM–EDS, XRD and FT–IR were applied to study the origin of its structure. The results of instrumental analysis and the archaeological context indicate that the adhesive substance investigated consists mainly of calcium carbonate (calcite, 78–88%), silica dioxide (quartz), sodium aluminium silicate (albite) and potassium aluminium silicate (microcline). The material might be a man‐made, mineral adhesive, a kind of lime mortar. The object is considered as the oldest European finding of this type outside the Mediterranean Basin. It provides evidence for the use of the lime calcination process in Central Europe as early as in the Late Neolithic, for which there were—up to now—no convincing premises.  相似文献   
10.
In 1973, while recovering copper cargo from a 20th‐century ship wrecked off the Ponta do Leme Velho on the south‐east side of Sal Island, Cape Verde, explosives revealed an earlier ship cargo with dozens of Portuguese faience plates and bowls, glass beads and metal objects, including buckles, ammunition and copper manillas. The assemblage, including the ceramics and a marked silver tastevin, provide a site date between 1680 and 1700. The research presented here is a result of collaboration between CPAS and the authors in 2008 to analyse this assemblage in the context of late 17th‐century maritime trade.  相似文献   
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