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51.
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   
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This study seeks to advance the understanding of the utility of “soft power” by exploring the case of Qatar. The country's approach is conceptualized as “nested power” through the examination of its political strategies before and after the regional blockade in 2017. The role of soft and nested power in Qatar has already been examined through various vantage points, such as small state diplomacy, mediation, and sports. Since the blockade has been for Qatar a great strategic dilemma, examination of how it affected power dynamics reveals the salience as well as the resilience of Qatar's soft and nested power. The article will discuss the concepts of “soft” and “nested” powers and their relevance to the state of Qatar in general and it will focus in the final section on the post‐blockade period. In doing so, we also seek useful approaches, which can be compatible with, and even advance “global international relations” (IR). The movement to make IR more global and inclusive is a welcome feature of the current century, reflective of the burgeoning role of the “Global South.”  相似文献   
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In 2010–11 a pedestrian survey of the western end of Wadi al‐Hijr in northern Oman identified 1507 archaeological features in a 124 km2 area. Data were collected on each feature's architectural characteristics, associated artefact assemblages, topographic and environmental locations, condition of remains, and relations to other archaeological features. The majority of datable features belong to the third millennium BC and divide unequally between the Hafit and Umm an‐Nar periods. While the majority of these third‐millennium BC features were tombs, other feature types were identified, including towers, settlements, quarries, dams, enclosures, and possible platforms. Third‐millennium BC features were organised into clusters and ranged considerably in size, from a few features to several hundred. All of the clusters established during the Hafit period were maintained in the Umm an‐Nar period, suggesting a continuity throughout the third millennium. Some preliminary hypotheses regarding settlement patterns are suggested.  相似文献   
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The Royal Artillery Factory of Seville in Spain originated from pre‐existing private bronze foundries dating from the 16th century. The paper analyses the stratigraphy of wall cladding in the areas traditionally known as the ‘Old Foundry’ and the ‘New Foundry’, through its characterization by optical microscopy, scanning electron microscopy with energy‐dispersive X‐ray spectrometry (SEM‐EDX), micro‐X‐ray fluorescence (μ‐XRF) and micro‐X‐ray diffraction (μ‐XRD), in order to analyse the metal deposits that have accumulated since the 17th century. The data obtained allowed the verification of the available historiographical information and the location of the original bronze smelting furnaces. The analysis of patinas deposited on the overlapping layers of lime also confirmed that neither the raw materials nor the composition of the alloys used presented any substantial changes.  相似文献   
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This paper presents a new method for estimating the amount of an artefact class in use at a given moment in the past from a random assemblage of archaeological finds. The method is based on the use of simulation, since an analytical solution is computationally impractical. Estimating the number of artefacts in use at any time t is shown to follow a Poisson distribution, which allows for credible intervals to be established using the Jeffreys prior. This estimator works from minimal assumptions about the dating and duration of finds, as well as the intensity of collection, and is applied to coinage from four Roman‐period sites excavated by the Roman Peasant Project (2009–14). The result provides an estimation of the abundance of material according to an interval of certainty.  相似文献   
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This study examines an ensemble of Romanesque churches in the region of Val d’Aran in the Spanish Pyrenees, built between the 11th and 13th centuries. Seven topographical studies performed between 2014 and 2015 examined these churches systematically using terrestrial laser scanning (TLS) as a data‐acquisition technique. The data obtained allowed for a geometrically accurate analysis of the orientation of these churches based on four Romanesque liturgies: Gemma animae (c.1120), by Honorius of Autun; Rationale divinorum officiorum (c.1150), by Jean Beleth; Mitralis de Officio (1190), by Sicard, Bishop of Cremona; and Prochiron, vulgo rationale divinorum officiorum (1291), by Guillaume Durand.  相似文献   
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