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71.
古代文物丝织品霉斑清除的研究 总被引:2,自引:1,他引:2
为了解决故宫博物院库房藏品中部分古代丝织品出现生霉的问题,从对库藏纺织品的病害现状调研入手,了解生霉文物本身的质地、染料成分、以及霉斑形成的环境状况,利用改进的改良型超声清洗方法和弱酸化水溶液,对多件霉变石青色丝织品进行了清洗处理,获得了满意的效果,此法可以在今后的工作中加以推广。 相似文献
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What if Edward Abbey's “Monkey Wrench Gang” had Succeeded? The Ghosts of Glen Canyon Past,Present, and Future 下载免费PDF全文
Laura Smith 《对极》2018,50(5):1396-1414
Across the fiction and non‐fiction writings of Edward Abbey (1927–1989), the anticipated restoration of Glen Canyon on the Colorado River is a recurring theme. This article employs Abbey's polemic for the removal of Glen Canyon Dam to critique contemporary debates on dam decommissioning, water politics, and ecological restoration in Glen Canyon on the Utah–Arizona border. The endeavours (and fantasies) of Abbey's fictional quartet of eco‐saboteurs reveal his radical and anarchical imaginings on how to remove the dam, yet his non‐fiction works often suggest why Glen Canyon should be restored. The politicisation of Abbey's philosophy is explored through (1) organisational, institutional responses to the question of draining Lake Powell reservoir and decommissioning the dam, and (2) how the ideology of Abbey's fictional gang is recast—and plays out—in the actions of environmental activists. This article argues that Abbey remains an important voice in the battle to restore the Glen. 相似文献
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采用层次分析法与熵权法相结合的方法,构建长株潭城市群城镇化综合发展水平和水资源开发利用综合潜力评价指标体系及响应关系模型,对2001-2015年间研究区域城镇化发展进程与水资源利用之间的动态过程进行定量研究,分析主要影响因素、变化特征以及两者响应特征。结果表明:长株潭城市群处于快速城镇化和规模扩张阶段,人口城镇化和空间城镇化水平高于经济城镇化和社会城镇化水平,城镇化发展质量有待提升;区域用水负荷逐年增加,虽然水资源利用效率和管理水平稳步提升,但水资源自然禀赋和开发利用程度受区域水文条件的影响显著。在2001、2005、2007、2009、2011年,长株潭区域城镇化的发展在一定程度上受到水资源系统的约束。协调好城镇化与水资源之间的关系,必须改变规模外延扩张模式,以控制水资源总量、有效提高水资源利用效率为目标,减弱水资源系统对城镇化发展的制约,提高水资源保障能力。 相似文献
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Mark Hayman 《The Journal of imperial and commonwealth history》2018,46(2):323-344
This article examines the economic and political impact of the Second World War upon a small outpost of Britain’s informal empire. It analyses the multiple ways in which the economy, trade and governance of the Trucial Coast were disrupted, disturbed and challenged by the exceptional circumstances of the war. In response to these circumstances, a variety of emergency arrangements were introduced, resulting in an unprecedented degree of involvement of outsiders and foreign agencies in the management of the local economy. The transformation of Britain’s traditional policy of non-interference in the internal affairs of the Trucial Coast is traced back to the exigencies of wartime conditions. 相似文献
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W. van Zeista 《Journal of archaeological science》1983,10(4):351-354
Foundation deposits underneath the walls of two temples near Semna, Sudan (c. 1500-1480 BC), included dried plant material. Five fruit species are represented: Vitis vinifera (grape), Ficus carica (fig), Citrullus vulgaris (water melon), Phoenix dactylifera (date) and Ziziphus spina-christi. Of particular interest are the remains of tubers of Cyperus esculentus. The plants mentioned above are known as funeral gifts in Egyptian tombs. 相似文献
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“Urban Ecology Under Fire”: Water Supply in Madrid During the Spanish Civil War (1936–1939) 下载免费PDF全文
This paper investigates the critical role of workers to enhance the resilience of water supply services in cities at war through analyzing the case of Madrid and the Madrid water company Canales del Lozoya during the Spanish Civil War (1936–1939). We argue that securing the protection of vital urban flows mediated through infrastructures is a key objective of cities under attack. In doing so we contend that examining how those affected by the interruption of these flows cope with the situation represents a valuable but largely neglected form of water management. We illustrate how quotidian knowledge about the urban geography of water flows may have important repercussions for the war effort itself. In a nutshell, the case of Madrid offers an early account of the critical role of water workers in sustaining “urban ecologies under fire” securing the complex urban metabolism while also contributing to the struggle against invading forces. 相似文献
80.
At Ocean Drilling Program Site 997 in Blake Ridge gas‐hydrate field in West Atlantic, pore‐water studies revealed a pronounced downward depletion of the heavy chlorine isotope to nearly ?4‰δ37Cl at approximately 750 m below sea floor (mbsf) associated with a 10% downward chlorinity decrease. This is one of the stronger 37Cl depletions hitherto reported for marine pore waters. Chlorinity reductions in hydrate‐bearing sediments commonly result from fresh‐water release by hydrate melting. However, in situ measurements at Site 997 suggest that >50% of the chlorinity reduction occurred prior to hydrate dissociation. Modeling the chlorinity profile shows that advection of a strongly 37Cl‐depleted, low‐chlorinity water (506 mm ) from below the drilled sequence can explain the reduction prior to sampling. Fitting the model to the δ37Cl curve yielded an advection rate of 0.18 mm year?1. Diffusive mixing with near‐0‰‐δ37Cl paleo‐seawater with maximum chlorinity at shallow subsurface depths (561 mm at approximately 20 mbsf) produced the smooth, steady trend. Separating that part of the freshening caused by advection and diffusion from that due to hydrate dissociation allowed estimation of average hydrate concentrations of 3.8% of the pore space (up to 24.5% in hydrate‐rich layers; near‐100% in rare massive hydrate layers). The deep‐seated source of the 37Cl‐depleted, low‐chlorinity water remains unknown and might be located below the sedimentary section in the oceanic basement. 相似文献