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1.
在明代,由于水患频发和长江主泓变动等原因,湖广武昌府城沿江江岸屡屡崩陷,当地政府遂启动江岸修筑工程。考诸史志,明代武昌府城的江岸修筑主要约有四次,分别是正统七年(1442)、成化三年(1467)、万历十七年(1589)和万历三十四年(1606)。最终修成的江岸,自武昌府城南门望山门外(今武昌解放路南端解放桥附近)起,向西折至江边,又沿江边中经黄鹤矶向下游延伸至坛角地区(今武昌和平大道武汉工人文化宫以西),长约5公里。这条堤岸确定了武昌城沿江江岸的基线,将武昌城的城市空间扩展到江边,并延续至今。  相似文献   
2.
The concentrations of two major elements and thirteen trace elements in 73 selected sherds of fine grey ware from the Iron Age and Roman period, excavated at Conimbriga, Santa Olaia and Tavarede, Portugal, were determined by instrumental neutron activation analysis. These concentrations were used to calculate distance matrices which were then subjected to cluster analysis employing SAHN and k-means methods, as well as to principal components analysis, to group the sherds according to the overall similarity of their compositional characteristics. The results showed that equivalent groupings appeared regardless of the taxonomic method used. Two major clusters were recognized corresponding to two different sites, namely Conimbriga and Santa Olaia, suggesting that the ceramics from these sites were made locally. No significant differences in compositional patterns were observed between iron age and roman sherds from Conimbriga.  相似文献   
3.
ABSTRACT

This paper will examine settlement location during the Iron Age in the northeast part of the Netherlands, an area shaped by Pleistocene geology. In recent years, a number of Late Iron Age/Early Roman settlements situated on the low lying slopes of sand ridges and nearby stream ridges revealed traces of an earlier Iron Age occupation. Palynological data revealed that this part of the landscape was used by humans before it was transformed into an area of settlement. An analysis of excavation data from two key sites at Denekamp-De Borchert and Groningen-Helpermaar, as well as other known sites, lead to the conclusion that the transformation of ‘peripheral landscapes’ into permanent settlement locations was preceded by a phase of arable cultivation which left no trace of permanent habitation. It is also suggested that the impact of human behaviour on the natural landscape in the Early and Middle Iron Age was much bigger than previously anticipated. When excavating this type of settlement areas dating to the Late Iron Age, archaeologists must be aware that only of a small group of archaeological features exist. The proposed model for the choice of settlement location may be more widespread, because of similarities in landscape between the study area presented here and other landscapes in Northwest-Europe (e.g. parts of Germany and Denmark).  相似文献   
4.
Metallurgical analyses and chemical characterizations were carried out on historical cannonballs from the Fortress of San Juan de Ulúa, Veracruz, México. Cannonballs dating from the 18th and 19th centuries share metallurgical characteristics similar to those of material coming from a shipment of ammunition found in the wreck of a sunken French ship from the battle of Trafalgar. The analyses show that the base material is grey cast iron with a carbon equivalent of 4.94 and a ferritic–perlitic matrix, in which the high phosphorus content has led to the formation of iron phosphide compounds in conjunction with a homogeneous distribution of carbon graphite flakes of Type C. In addition, corrosion products from samples revealed the presence of various crystalline iron compounds (X‐ray diffraction), mostly highly chlorinated iron compounds identified as akaganeite. X‐ray fluorescence identified various characteristics of the corrosion products as a function of the sampling depth. FT–IR spectroscopy revealed that the main difference between the corrosion products (internal and external) is determined by the number of organic species. Differential scanning calorimetry corroborated that these corrosion products are thermally stable compounds at elevated temperatures.  相似文献   
5.
The Akko 1 shipwreck was an Egyptian armed vessel, built at the beginning of the 19th century. A wooden saw handle and a box containing iron nails and two split pins were discovered towards the stern. Given their function, location and context, these were part of the ship's carpenter's tools and accessories. A methodology was developed for conducting systematic metallurgical analysis in order to understand the manufacturing process of the surviving ironwork items, as well as to enlarge our knowledge regarding ironworking technologies during the early 19th century. Such methodology may assist in the future understanding of the technological evolution of similar wrought‐iron objects. The results demonstrated that the artefacts have a wrought‐iron heterogeneous microstructure and were manufactured by hot‐working prior to surface hardening by pack carburization.  相似文献   
6.
Ancient iron tie-rods are handcrafted elements with large geometric irregularities, due to production techniques (they are shaped by hammering and linked by hot-forging) and corrosion processes. In common practice, their cross section (that is one of the main parameter to assess their strength) is manually measured on site with a manual caliber. By analyzing a set of detailed three-dimensional (3D) digital surveys of real ancient tie-rods, this study provide an evaluation of the errors made by in-situ manual geometric measurements. In particular, it shows that, in some cases, manual on-site survey is sufficiently reliable and has errors that fall below 10%. Moreover, it shows that when tie-rods have high corrosion levels in hidden zones (typically those close or within the retaining walls) the on-site survey of visible parts only may produce far greater errors that exceed 100%, leading to a strong overestimation of the cross-section of the tie. The ongoing study is a first step toward the definition of correction coefficients to be applied to the on-site manual measurements of ancient tie-rods, with the final aim to improve the reliability of structural analyses.  相似文献   
7.
The use of metal tie-rods in buildings is documented and visible in many Italian areas since the 15th century. This article refers to the study of treatises, manuals and essays from the 15th to the early 20th century, mainly in the Italian context with some exceptions of certain foreign texts that, due to their diffusion and importance, have greatly influenced the technical literature on the subject. Technology is an expression of the social, economic, cultural, political and juridical events of a country and, as such, is deeply linked to the times and territories in which it develops. However, it is also closely linked to the laws of nature and to forms of communication, therefore it is useful to compare, underlining the analogies and differences, the knowledge and the ways of the productive and technical process in a long-term analysis.  相似文献   
8.
The emergence of anti-democratic movements is a central puzzle to social science. We study a novel and rich historical dataset covering Swedish municipalities during the interwar years and find a strong link between the presence of a military garrison and the emergence of fascist parties. We interpret these results as suggesting that fascist mobilization in Sweden was driven by discontent with the process of disarmament brought about by democratization. In contrast, poor economic conditions, as captured both by levels of and changes in the local poverty rate and tax base, do not explain the strong link between the fascists and military garrisons. We relate these results to influential theories of democratization.  相似文献   
9.
This article narrates the role of oral testimony in the fieldof Abraham Lincoln studies from 1865 through the 1930s. Collectedin the form of letters, affidavits, and face-to-face interviews,this mounting body of "eyewitness evidence" dominated the discoursefor two generations and reflective, public practice culminatedin the organization of a "Lincoln Inquiry" in the Midwest duringthe 1920s and 1930s. For a time, practitioners successfullydefended themselves against increasing positivist assaults onthe credibility of oral testimony. Their interests and effortsresonate with later oral history practice and theory about method,authorship, performance, and memory, and their story highlightsthe contingency inherent in the development of oral historicalpractice in America.  相似文献   
10.
The delphinal counsellor Mathieu Thomassin composed a Breviere des anciens droys … du Dauphiné de Viennoys (c.1453) after a career of 30 years in the service of Charles III (the French king Charles VII) and Louis II (the future Louis XI). This was his first major historical text in French, but has been overshadowed by his better-known Registre delphinal, commissioned by Louis II in 1456. This article analyses the historical culture and the conception of history revealed in the Breviere. It notes how Thomassin's careful definitions of frontiers in the past and present reflect his experience of territorial disputes. History and geography are imbued with polemic, however, allowing Thomassin to override competing claims to territory or autonomy by delphinal opponents within and outside the Dauphiné. The principles set out in the Breviere were refined and extended in the Registre. However, it is unlikely that either work was ever intended for wide circulation; rather, they were written to provide ‘authentic’ texts which could be consulted primarily by other delphinal officers. As such, they reflect on occasion the divergence of views between a proto-professional administrator, with a concern for the long-term, and his preoccupied (if not dilettante) prince, much more subject to the requirements of realpolitik.  相似文献   
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