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排序方式: 共有187条查询结果,搜索用时 15 毫秒
1.
许多出土饱水木质文物因其降解严重、含水率较高,容易在脱水过程中出现不可逆的收缩变形以及开裂现象,从而遭到严重破坏。因此,饱水木质文物脱水方法的研究是文物保护工作中的重要课题。为探究风冷冷冻法对饱水木质文物脱水的效果,以一批无法复原的出土饱水木质文物为研究对象,在对其材种、含水率、基本密度及化学成分进行了测定和分析后,使用一台风冷电冰箱在-18℃条件下对样品进行了风冷干燥脱水处理,记录脱水时间和脱水效果,并分析了该方法的传质传热特点,证明了风冷干燥法用于饱水木质文物的脱水干燥能够取得良好效果,并且具有对文物干预小、适用性广、操作简便、成本低廉等优点,为饱水木质文物的脱水处理提供了一种新的思路。  相似文献   
2.
Two sets of twelve Portland limestone tablets were attached to carousels outside and under the open, lightweight shelter at Bishop’s Palace (Witney, England) for 18 months to assess the influence of shelters on soiling and microbiological growth on stone. At the start, and at 6-month intervals, tablets were analysed using microscopy (optical and SEM), colour measurement (spectrophotometry), weight change measurement and salt content determination (ion chromatography). Concentrations of NO2 and SO2 were also monitored for a month using diffusion tubes. In addition, results were compared with those obtained by the UK National Materials Exposure Programme (NMEP) on chemical weathering rates. Differences in soiling and biological growth on sheltered and unsheltered samples, and their influence on limestone decay were established. The shelter is likely to reduce biological growth by modifying the micro-environmental conditions. However, it may also exacerbate dust deposition, which might increase decay rates in the long-term.  相似文献   
3.
Methodological advancements in geoarchaeology and spatial and chronological modeling are opening new avenues to interpreting large coastal shell-bearing sites. We document the developmental histories of two such sites around Prince Rupert Harbour, Canada, using systematic percussion coring, intensive radiocarbon dating, and 3D surface mapping with Total Station and LiDAR. We also re-analyze a third site (Boardwalk/GbTo-31) excavated and radiocarbon dated in the 1960s, 1970s, and early 2000s using archival field notes, site maps, and stratigraphic profiles georectified using LiDAR. We map the natural landform beneath the sites and document the degree to which people physically modified landforms through the deposition of massive shell accumulations. We model site development through time and space and use accumulation rates and OxCal modeling to test for intentional deposition events. All three sites demonstrate complex and heterogeneous occupation histories. At each we identify instances of very rapid deposition that effectively terraced and extended parts of the natural landform to create places for constructing houses, though these episodes take place within longer histories of slower quotidian deposition. The anthropogenic modifications to the coastline in this area are the result of these mixed processes associated with long histories of occupation.  相似文献   
4.
While the links between contaminated sites and adverse effects on human health and well‐being are being increasingly recognised, some argue that the magnitude of the health problem is inadequately addressed because it is largely invisible. Health geographies literature has sought to highlight this invisibility by focusing on the link between contaminated sites and health. This study adds to health geographies by presenting unique insights into the geography of residents' worry about the disruptive effect of environmental contamination on health and well‐being. It analyses a sample of residents (n = 485) living near 13 contaminated sites across Australia. Ordinal logistic regression analysis of closed‐format survey questions was combined with coding of open‐ended survey questions to reveal the geography of residents' worry about contamination from nearby sites. First, the study explores some of the main relationships between residents, their environs, and contaminants from nearby source sites, which determines their levels of worry: residents' demographics, residents' proximity to sites, contaminant boundaries and borders, and type of contaminant. Second, the study investigates how worry affects residents' health and well‐being, ranging from effects on their personal functioning through to their sense of ontological security, which depends in part upon their perceptions of contaminants' impacts. Despite having identified a range of diverse and negative effects of worry about contamination on residents, we found that worry for contamination can also prompt coping strategies and problem‐solving, reinforcing the need for more research on this subject.  相似文献   
5.
2015尼泊尔地震对加德满都谷地的世界文化遗产造成不可估量的损失。为了探究谷地文化遗产震害整体分布特征,对谷地世界文化遗产建筑的震害状况开展实地调查,划分了三类文化遗产震害等级标准,形成了六处世界文化遗产的震害图并对其进行统计分析,加德满都、帕坦和巴德岗三处杜巴广场震后保存基本完好的文化遗产建筑占各自总数的39.5%、53.3%、50%,斯瓦扬布纳特寺、昌谷纳拉扬寺和博达哈大佛塔主体保存基本完好,附属建筑不同程度地破坏。加德满都、帕坦和巴德岗三处杜巴广场地层的松软沉积层放大地震效应使建筑严重破坏,斯瓦扬布纳特寺、昌谷纳拉扬寺震害主要受地形特征影响。考察成果为我国同类遗产建筑的抗震防护提供参考。  相似文献   
6.
Ancient places of performance are often considered for reuse as a means of promoting archaeological sites. Therefore, local authorities and decision makers have a difficult task of balancing the conservation and management of the sites with the carrying capacity. In this paper, the bouleuterion, a ‘rediscovered’ structure, at the Teos archaeological site, in Turkey is evaluated and presented as a preliminary case study with the hopes that these issues will be taken into consideration by the managing body in the creation of a management plan for the site. The evaluation is made by assessing socio-economic and intangible heritage significance, policies guiding changes at the site, a qualitative survey at the site and by defining the structure’s carrying capacity. The site’s strengths, weaknesses, opportunities, and threats are used to create criteria and make proposals for its reuse. The study concludes that the bouleuterion cannot be reused as a venue in its present condition and makes recommendations for future use.  相似文献   
7.
Ethnoarchaeological observations at Maya shrines on a sacred mountain suggest that three potent material strategies imbue ritual practices with different social meanings: 1) the use of different types of materials as offerings in various rites, 2) the ways in which the physical conditions of an offering are altered during deposition, and 3) the choice of location where the offering is deposited within the site relative to a ceremonial focal point. Through these strategies, individuals creatively negotiate limited access to material resources and assign diverse meanings to the material culture, practices, and places of ritual. Materials that represent commoners' rituals may primarily consist of quotidian items that are transformed in meaning by how and where they are deposited into an archaeological context.  相似文献   
8.
宁绍地区史前文化遗址地理环境特征及相关问题探索   总被引:3,自引:0,他引:3  
本从宁绍地区各个遗址不同时期遗存的海拔数据对比入手,试图找出距今7000至4000年间遗址环境变迁的规律,并从化生态学角度去分析、解释、推断诸如河姆渡化“缺环”说、宁绍地区7000年前古化地理环境、宁绍地区史前化遗址环境与聚落形态特征的关系等问题。  相似文献   
9.
Excavated human bone was exposed to aqueous solutions containing high concentrations of a single added metal ion in order to examine the extent of introduction of contaminating materials during burial. Variables included pH, temperature, ion concentration, state of bone (whole or crushed), structure of buffer, and counterion. Calcium and sodium showed little increase, and even a decrease in some cases. Strontium, zinc, lead, and magnesium showed large increases probably through heteroionic replacement of calcium. Manganese, aluminum, and potassium showed increases, particularly under neutral conditions, probably through infiltration into voids and defects.  相似文献   
10.
The interaction between the Swahili Coast of the present-day Tanzanian coast and other parts of the Indian Ocean world dates back to the first millennium AD. This commercial communication resulted in the rise of several coastal city-states (stonebuilt towns), some of which date back to the tenth century. Unfortunately, some of these states started to collapse during the second half of the second millennium and the majority of them is in a ruinous state. These material remains, which according to the Tanzania’s Antiquities Act of 1964 deserve legal protection, have not been studied comprehensively mainly to establish their conservation history. The current article addresses this problem, and by analysing documents, it establishes the conservation history of monuments and historic buildings of the Swahili Coast in Tanzania. Research results indicate that some built heritage sites started decaying during the fourteenth century AD. Because of recognising the importance of these built heritage sites, communities of the region embarked on strategies to care these built heritage sites. This observation contradicts the European conventional wisdom maintaining that, in Africa, conservation of built heritage sites such as monuments and historic buildings began in the nineteenth century and was propagated by European colonialists.  相似文献   
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