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1.
The aim of this investigation was to analyze the materials and techniques of the paintings in the 16th-century ce St Mary's Church, to evaluate deterioration of the paintings, and to propose a suitable conservation treatment for their preservation. The material analysis of ground, pigments, binders, and plasters was undertaken using binocular microscopy, field emission scanning electron microscopy (SEM)–energy dispersive X-ray spectroscopy, X-ray fluorescence, Fourier transform infrared spectroscopy in reflectance (KBr) and transmittance mode (attenuated total reflection), thin-film X-ray diffraction, and micro-Raman spectroscopy. Gas chromatography–mass spectrometry (GC-MS) was used for identifying proteinaceous and lipidic materials extracted from the micro-samples. The study generated data on two different red and green pigments used as decorative materials. The red pigments were identified as cinnabar along with traces of hematite and clay minerals, and green as malachite and the minor presence of other minerals. SEM analysis identified cotton fiber embedded in the coarse plaster layer that provided better strength to the plaster. Plant oils and proteins found as the binder in the pigment samples suggested that the painting technique was executed as tempera. Lead white and gypsum materials were used in previous restoration works. 相似文献
2.
Matthew Quick Tanya Christidis Toyib Olaniyan Nick Newstead Lauren Pinault 《The Canadian geographer》2023,67(3):352-365
Cooling centres provide respite, safety, and social support during extreme heat events for populations that do not have the resources to own or operate in-home air conditioning. The objective of this study was to measure the spatial accessibility of cooling centres and analyze the associations between cooling centre access and marginalization in Montreal, Toronto, and Vancouver, Canada. The potential spatial accessibility of cooling centres within a 15-minute walk was measured at the dissemination area scale using the two-step floating catchment area method. A two-stage modelling approach was used to analyze the associations between cooling centre access and marginalization. Approximately 62%, 58%, and 54% of the populations in Montreal, Toronto, and Vancouver had access to at least one cooling centre. In Montreal and Vancouver, high marginalization areas were more likely to have cooling centre access than low marginalization areas. Of the areas with cooling centre access, smaller access scores were observed in areas with high residential instability. Approximately one-fifth of the areas in each city had no cooling centre access and high marginalization, and may be considered for future cooling centres or programs that improve accessibility to existing centres. 相似文献
3.
First Insights into the Technique Used for Heat Treatment of Chert at the Solutrean Site of Laugerie‐Haute,France
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The earliest evidence of flint and chert heat treatment was found in the ~21.5–17 ka old European Solutrean culture. The appearance of pyrotechnology as part of the production of stone tools has important implications for our understanding of Upper Palaeolithic technological evolution and the specific adaptations during the last glacial maximum in Europe. However, the techniques and procedures used to heat‐treat rocks during the Solutrean remain poorly understood. No direct archaeological evidence has so far been found and the most promising approach is to understand these techniques by determining the parameters with which flint and chert were heated at that time. In this study, we investigate the heating temperature of 44 heat‐treated laurel‐leaf points from Laugerie‐Haute, using a non‐destructive technique based on infrared spectroscopy. Our results document that most of the artefacts were heated to a narrow interval of temperatures between 250 °C and 300 °C. This indicates a standardized technique that allowed to created similar conditions during successive heating cycles. The implications of these results for our understanding of the technical complexity during the Solutrean must be discussed in the light of different heating techniques used at different places and periods. 相似文献
4.
Michael Marder 《Political Theology》2015,16(2):146-158
AbstractIn this article I argue that the ideal of rationality espoused by the European Enlightenment hinges on the separation of the light of reason from heat, with which it had been conjoined in the classical element of fire at least since the Greek antiquity. As a result, evil, from the standpoint of the Enlightenment is tantamount to heat without light, while evil, critically viewed outside this tradition, inheres in the absolute separation between the two aspects of the life-giving, albeit ineluctably dangerous, fire. 相似文献
5.
目前对文物保护的研究主要以试验为主,本研究试图用数值方法分析文物展柜的动力学特性,以解决试验分析方法所导致的缺陷。为此,对固定和浮放两种不同边界条件的文物展柜进行地震作用和简谐激励下的动力响应分析,给出了展柜展台面处的加速度动力放大系数(简称放大系数)上限值。以某博物馆展柜为原型,按1∶1/0.39进行缩尺振动试验,得出两种边界条件下展柜展台面处的放大系数。对试验展柜建立有限元模型,通过与试验对比,验证模型及分析方法的正确性。然后,建立展柜模型的有限元模型,对5种尺寸的展柜进行了动力响应分析,并考虑激励幅值、激励频率等对放大系数的影响。分析结果有助于指导文物的防震保护工作。 相似文献
6.
R. Alan Covey 《Journal of Archaeological Research》2008,16(3):287-338
During the Late Intermediate period (LIP, c. A.D. 1000–1400), the central Andes experienced the decline of the Wari and Tiwanaku
states, as well as processes of state formation, regional population growth, and competition culminating in the imperial expansion
of the Chimú and Inka polities. The LIP holds the potential to link the archaeological features of early Andean states with
the material signatures of the later ones, providing a critical means of contextualizing the intergenerational continuities
and breaks in state structures and imperial strategies. The recent proliferation of LIP research and the completion of a number
of regional studies permit the overview of six LIP regions and the comparison of highland and lowland patterns of political
and economic organization, social complexity, and group identity. 相似文献
7.
P. Holck 《International Journal of Osteoarchaeology》2008,18(2):188-194
During the 1991–1992 excavation of the ruins of the medieval cathedral in Hamar, Norway, the broken skull of an elderly man was found, showing evidence of an incomplete trepanation. The ‘surgeon’ had obviously tried to penetrate the skull surface around bregma in an irregular circle of 23 × 21 mm. Upon investigation, the skull revealed a reactive‐pathological area of the internal surface of the occipital bone, which probably represents a respite after a meningeal disorder (a tumour or an infectious process), causing us to suggest that the trepanation was meant to cure the patient's increasing headache. However, as a second skull with similar marks was found in the same churchyard, another explanation seems possible. Because the brain tumour in the first case may have altered the patient's mental state, we may surmise that these incomplete operations were an attempt to remove from these patients' heads the ‘Stone of Madness’, which was then commonly considered to be the reason for psychiatric diagnoses as well as persistent headache, and often depicted in European art, most notably in the 16th and 17th centuries. The second skull, revealing an even more incomplete attempt, did not show any skeletal pathology at all. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
8.
Nyree Finlay 《Journal of Archaeological Method and Theory》2008,15(1):68-90
Skill is central to the identification of the individual within lithic analysis. Modern replication tends to focus on the
proficient flintknapper, and emphasises complex, technically demanding implements and high quality raw materials. Yet, acquiring
lithic skill is a universal process that manifests itself in various ways depending on technological strategy and raw material.
This paper presents the results of a programme of experimental replication that explores notions of consistency and identity.
Based on Mesolithic blade technology, using direct percussion reduction and variable pebble resources, it compares knappers
with different experience and identifies some salient parameters of individual performance. 相似文献
9.
Two‐phase flow and near‐critical phenomena are likely to enhance energy transport in high‐temperature hydrothermal systems. We present a series of two‐dimensional simulations of two‐phase flow of pure water at near‐critical conditions. The results show that at near‐critical conditions, two‐phase convection can be more efficient in transporting energy than single‐phase convection. The highest heat fluxes are attained when two‐phase heat‐pipes form near the bottom boundary, recharging the root of the upflow zone and thereby enabling the formation of broad upflow regions. When the system becomes more vapor‐dominated, it loses this ability, upflow zones become narrower and the energy efficiency drops to more moderate values. 相似文献
10.
大力发展三江源地区的医疗卫生事业,不断提高人民群众的健康水平,对于加快生态文明建设,推动环境保护,促进人与自然和谐相处,统筹经济社会全面协调可持续发展,着力改善民生,使该地区与全国同步实现全面建设小康社会目标,都具有十分重要的意义。本文在概要阐述三江源地区医疗卫生事业发展现状与特征以及政府公共卫生政策措施与效应的基础上,提出推动该地区医疗卫生事业可持续发展的若干公共政策建议。 相似文献