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1.
The study implements the performance-based analysis and design methodology to assess the seismic vulnerability of a coal-fired power plant and to optimally design its equivalent pendulum-type tuned mass damper system such that the direct losses are minimized. A building-specific total loss ratio is developed to link the component level losses with the total repair cost of the original structure. The optimal system configuration is finally derived for cases with the minimum loss. The study demonstrates a systematic way of achieving the optimal pendulum-type tuned mass damper design with considerations of uncertainties in earthquake inputs and the combined component level damages.  相似文献   
2.
在植物对土遗址作用的研究中,鲜有就真实的遗址来展开调查,以及讨论植物给土遗址带来的负作用及其机理。为此,本研究选取西安地区大型土遗址秦阿房宫为研究对象,利用现场调查结合样带法、图像分析法并采集土样,开展对遗址区植物分布、根系产生的裂隙和土壤环境的研究。结果表明:造成土遗址病害现象的主要原因为植物根系作用,加之雨蚀、风化作用及人为破坏的叠加作用,使遗址保存面临严重威胁;其中酸枣、臭椿等萌生树种所产生的根劈裂隙及植物根系对土壤环境的影响十分明显。现存土遗址由植物以及风雨作用而引发的主要病害,其类型包含了边缘夯土的基础掏蚀、洞穴遗存、开裂坍塌、冲沟发育、表面剥蚀,这些是阿房宫遗址面临的主要威胁,也是半干旱地区土遗址存在的特有问题。研究结果既有助于揭示植被对土遗址的作用机理,又能为土遗址保护的植物选择提供理论依据和技术支撑。  相似文献   
3.
The chemical compositions and microstructures of some 35 faience objects from Egypt spanning the period from the Middle Kingdom through to the 22nd dynasty are determined using analytical scanning electron microscopy. Replicate faience beads glazed in the laboratory using the efflorescence and cementation methods are similarly investigated. In efflorescence glazing, there appears to be preferential efflorescence of soda over potash, and in cementation glazing, preferential take up of potash over soda into the glaze. These data are then used to try to infer the raw materials and methods of glazing employed in the production of the ancient faience. The glaze/glass phases present in the faience differ significantly in composition from that of New Kingdom glass. This could be due either to the use of different plant ashes or to changes in the composition of the plant ashes during the production of faience and/or glass. Although it is only rarely possible to determine with certainty whether ancient faience was glazed by efflorescence, cementation or application, the observed microstructures provide an indication of the approach adopted to achieve desired performance characteristics such as strength.  相似文献   
4.
Our blind tests are distinctive for they were conducted on replicated stone tools used for a variety of tasks that included the processing of animal remains and plants. The analyst was required to differentiate an array of residues from microscopic morphological characteristics, using light microscopy. The original aim of our first tests was to assess the analyst's ability to identify a variety of plant and animal residues, but issues and problems that arose during the testing process made it clear that greater value might be gained from the lessons that we learnt about methodology and the direction for future micro-residue research. We show that problems identified during our first tests stimulated research. Amongst other things, we learnt to distinguish plant and animal remains more confidently than previously. Our residue analyses are firmly embedded in wider archaeological research and our tests help to explain why there are sometimes contradictions between the evidence from archaeologically recovered remains and residues on stone tools. A further outcome of the tests is that we have adopted a multi-stranded approach that provides a cautious, but secure strategy for identifying and interpreting use-residues. Our studies of contaminants through replications have also been invaluable for distinguishing incidental residues from use-related residues.  相似文献   
5.
1999年以来 ,新乡市文物工作队在市区内几个地点共发掘 7座唐代墓葬。墓皆为砖室 ,可分为长方形多室墓、长方形单室墓和方形单室墓三种。这批资料为研究新乡地区唐代的社会经济有较重要的价值  相似文献   
6.
2003~2004年,新乡市文物考古研究所发掘了新乡市火电厂251座战国晚期至西汉晚期墓葬,出土一批精美的彩绘陶器、大型铁制生活用品、铜器等遗物.根据墓葬形制和随葬品组合,将墓地分为五期,从战国晚期至西汉晚期,为研究中原战国至汉代文化提供了珍贵的实物资料.  相似文献   
7.
The analysis of phytoliths, pollen, charcoal and other macroremains was carried out in the neolithic shelter of “La Grande Rivoire”, Vercors massif (French Alps). The results show the predominance of tree species, in the form of phytoliths, clustered pollen, stomata, small branches charcoal, needles, bark, buds… The practice of leaf fodder is already known in the alpine and circum-alpine area from archaeological and historical sources. The analyses of the neolithic dung levels of “La Grande Rivoire” illustrate the use of leafy and flowering tree branches as fodder. The results also suggest that some species were used for special purpose in relation with the tending of livestock (litter, dietary supplement, veterinary practices).  相似文献   
8.
Plant microfossil analysis was carried out on 12 soil samples from a variety of landscape features at three locations (100–250 m a.s.l.) along a 950 m transect at Te Niu, Easter Island. Pollen and phytolith assemblages were dominated by palms and ground ferns, and suggested disturbed forest. We identified pollen of bottle gourd (Lagenaria siceraria) and starch grains of the common yam (Dioscorea alata), sweet potato (Ipomoea batatas) and taro (Colocasia esculenta). The data suggest a mixed-crop, dryland production system at Te Niu dominated by yam and sweet potato, and supplemented by taro and bottle gourd. The data provide direct evidence of crop type and range, supporting the indirect evidence (topographic and landscape features, field and historical research, comparisons with elsewhere in the Pacific) that much of the rock covered landscape of Easter Island was used for intensive horticulture.  相似文献   
9.
Pollen analyses of 13 archaeological sites in the Wadi Teshuinat area, in southwestern Fezzan, Libya, were synthesised to explore the potential contribution of palynological investigation to archaeological research in this area. During the Holocene, the sites were occupied by pre-Pastoral (hunter–gatherers) and Pastoral (pastoralists) cultures. Different pollen stratigraphies and floras characterised the diverse sites and the relevant cultural phases. Pollen data were reported by discussing the sites separately, and by combining them to interpret the regional data set. Emphasis was made on the anthropogenic pollen indicators and grasses, including large grass pollen grains (>40 μm), which were considered evidence of plant transport into the site. These were ethnobotanical markers, human-made evidence of plant harvesting by hunter–gatherers, or of animal breeding by pastoralists. The disappearance of some wild cereals was also observed, consistent with increasing climate dryness and land exploitation. Macroremains were used as a parallel tool to better understand plant exploitation in the region.  相似文献   
10.
There is a long history of human interaction with plants of the Aroideae subfamily (Araceae). Despite these plants' chemical defenses against animal and vegetal predation, humans have targeted their starchy corms, tubers and rhizomes for dietary purposes. In the Eastern Woodlands of North America, early Europeans described the Native population as utilizing the highly acridic Peltandra virginica (arrow arum) for subsistence needs. In order to render this resource edible, however, the acridic principle first needs to be eliminated. Our study investigates the affect these processing activities have on the integrity of arrow arum starch grains. Findings from this study demonstrate that environmental variables specific to individual processing procedures may be more influential on starch grain survival than simply the temperatures reached during cooking.  相似文献   
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