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1.
高颐阙是东汉晚期的红色砂岩的建筑物。位于四川省雅安市。阙檐东面残缺.导致日晒雨淋加剧,苔藓丛生,从而引起严重风化。为此,对残损阙檐进行了修复。根据高颐阙的结构.雅安市的气候特征及阙石的化学组成和物理性质.讨论了薄片检查和 X 衍射分析的结果、修复残缺阙檐的理论基础以及计算、修复的程序和效果。  相似文献   
2.
ABSTRACT

Along Florida’s nearly 13,000 km of shoreline, nearly 4000 archaeological sites and over 600 recorded historic cemeteries are at risk from climate change impacts including coastal erosion and a 2-metre rise in sea level. In 2016, the Florida Public Archaeology Network (FPAN) created the Heritage Monitoring Scouts (HMS Florida) programme to engage the public in monitoring sites at risk. The programme grew quickly during the first year of operation to include 233 volunteers who submitted 312 monitoring forms. The programme exists beyond the singular act of a volunteer reporting site conditions; across Florida, varied combinations of local partnerships present unique opportunities for programmes, for example, the pilot program at the Guana Tolomato Matanzas National Estuarine Research Reserve. Preliminary outcomes from the first year of HMS Florida and the pilot indicate the programme is effective in public engagement and a powerful management tool for tracking change to sites over time.  相似文献   
3.
Invasive vegetation species can lead to major changes in the geomorphology of coastal systems. Within temperate estuaries in the southern hemisphere, especially Australia and New Zealand, the cordgrass Spartina spp. has become established. These species are highly invasive, and their prolific growth leads to the development of supratidal environments in formerly intertidal and subtidal environments. Here, we quantified the impact of Spartina invasion on the geomorphology and sequestration capacity of carbon in the sediments of Anderson Inlet, Victoria, Australia. Spartina was first introduced to the area in the 1930s to aid in land reclamation and control coastal erosion associated with coastal development. We found that Spartina now dominates the intertidal areas of the Inlet and promotes accretion (18 mm/year) causing the formation of over 108 ha of supratidal islands over the past 100 years. These newly formed islands are calculated to potentially contain over 5.5 million tonnes of CO2 equivalent carbon. Future management of the inlet and other Spartina‐dominated environments within Australian presents a dilemma for resource managers; on the one hand, Spartina is highly invasive and can outcompete native tidal marshes, thereby warranting its eradication, but on the other hand it is likely more resilient to rising sea levels and has the potential for carbon sequestration. Whether or not the potential advantages outweigh the significant habitat change that is anticipated, any management strategies will likely require additional research into costs and benefits of all ecosystem services provided by Spartina including in relation to nutrient cycling, shoreline stabilisation, and biodiversity as well as in response to the longevity of carbon found within the sediments.  相似文献   
4.
This paper examines the theory and practice of the maritime cultural landscape in general, and projects the theoretical concepts and aspects involved on the highly dynamic late medieval north‐eastern Zuiderzee region in the Netherlands. The cultivation of land and marine erosion (floods and rising sea level) are considered as the main factors that caused the transformation of the physical landscape of this region from peatlands with freshwater basins into a tidal lagoon. As a consequence, multiple settlements drowned, large areas of land submerged, and culture and the landscape gradually became more maritime, giving the research area a cultural identity and dimension.  相似文献   
5.
Kicking in soccer has been the subject of scientific research for more than 40 years yet review articles summarizing the biomechanical fundamentals of kick optimization as a guide to coaching are scarcely to be found. The current review article aims to bridge the gap between scientific research into the maximal instep kick (including studies employing 3D motion capture and full-body biomechanical modelling) and the application of such research in coaching. It does so by supplying a scientifically founded, coaching-friendly article explaining identifiable characteristics and motor control sequencing that define this skill. Relevant biomechanical factors are identified in a way that should help coaches better develop training programmes and, at the same time, foster better understanding of the skill among athletes. Such information will contribute to both accelerated skill acquisition and, by concomitant gains in skill efficiency, the development of programmes that minimize risk of injury to athletes during training.  相似文献   
6.
This article explores the linguistic experiences of transnational soldiers, using the Spanish Civil War as a case study. It argues that communication difficulties provoked by linguistic diversity within the Republican war effort and particularly within the International Brigades, caused the high command to move from a utopian, internationalist policy to a more pragmatic approach. The article evaluates the role played by language intermediaries in this evolving policy and in the wider Republican war effort. Finally, it argues that soldiers grassroots experiences of language contact forged new linguistic forms which underlined a strong sense of shared purpose and identity.  相似文献   
7.
Abstract

During the second stage of the East Asian War, Toyotomi Hideyoshi 豐臣秀吉 hopefully sought to make an honorable exit, but the Choson 朝鮮 formulated a unique diplomatic strategy that brought the Ming to the battlefield, and there was no way for Toyotomi Hideyoshi's retreat and attempts at peace talks to be successful. In the end, the war concluded with Toyotomi Hideyoshi's death from illness and the retreat of the Japanese army in defeat, and the international order established between China and Korea was maintained.  相似文献   
8.
Human and domesticate animal bone collagen δ15N values in prehistory differ generally by 3‰ or more from Neolithic to post- Roman times in Northwest Europe, leading to an assumed dietary animal protein fraction of 60–80% using a standard interpretation of δ15N values. We examine the assumptions on which this model rests and the limitations of our knowledge in the analysis of δ15N values in archaeology. We have developed a set of models which, with small changes made in assumptions (on the order of 1‰), can produce substantially lower estimates of the dietary animal protein fraction for given δ15N values. We consider the implications of various dietary animal protein fractions on agricultural carrying capacities and human population densities in prehistory.  相似文献   
9.
在冷战的国际大背景下,尼克松政府对苏实施的“缓和”战略使得华盛顿打出“中国牌”,致力于改善同北京的关系。而1969年3月中苏边界武装冲突则为美提供了一个契机。在寻求同中国对话的渠道上,华盛顿首先想到的是华沙渠道,即第135次和136次中美大使级会谈,并为此做了充分的准备。尽管史实证明:华沙渠道的进展不像华盛顿期望的那样顺利,但基本上完成了预期的任务:表达了改善对华关系的愿望,并阐明了不会同苏联合作主宰东亚事务的立场。在华沙渠道完成了既定任务之后,华盛顿又将同北京的联络转为巴基斯坦渠道。  相似文献   
10.
唐代县的等第,以户口、官品、俸秩、迁转次序等不同的标准看,有四等、五等、六等、七等、八等、十等诸说。从历时性而言,县等是不断增多的,由前期的六等逐渐发展到后期的十等,只是天宝时曾一度事实上取消下县,稍显波折。而望、紧、次赤、次畿县的出现,均与户口多寡无直接关系,更多地体现出“资地美恶”的特征。其中“次赤县”的问题尤其复杂,因其牵涉“赤县”的广义和狭义问题,综合分析,次赤县制度在传世文献中出现,不晚于唐德宗初年,很可能最迟代宗初期已经产生。而代宗末年至德宗前期形成的俸秩,对唐后期乃至五代的县之等第,也有新的影响。五代皆以户口多少定县的等第,只是不同王朝有不同的标准,繁简不一。通观唐五代县之等第,总体上呈现出从官品本位到以俸秩为准的演变路径。  相似文献   
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