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91.
A multi-technique characterization and a provenance study of the black pigment used in Cucuteni pottery painting (Neolithic age, Romania) were carried out. 127 Cucuteni shards were analyzed by Raman spectrometry. The main components of this pigment are pyrolusite and/or jacobsite. Hematite and quartz are frequent minor components and Ti oxides were seldom found. The manganiferous corpuscles discovered at Neam? county (eastern part of Romania) were the raw material of the Cucuteni black pigment. The Mn corpuscles were studied using XRD, Raman, FT-IR and Atomic Absorption Spectrometry. The main components are birnessite, goethite and frequently, quartz. Raw material was subjected to a temperature of 750 °C for 6 h and,once cooled, analyzed through Raman and FT-IR spectrometry. Pyrolusite, hematite and quartz were found in the heated powder sample.  相似文献   
92.
Abstract

The modern period of chart making in Russia began in the reign of Peter the Great. Peter created the country's navy, which became the main focus for cartography in the eighteenth century. In this paper the multi‐faceted duties of naval officers in the charting and mapping of seas, rivers, forest resources and other features important for ship building and the development of navigation, and essential to Russia's geo‐political interests, are considered. The history of the early stages of specialized naval education and the training of surveyors at the Moscow Mathematical‐Navigational School (from 1701) and the St Petersburg Naval Academy (from 1715) are outlined, and the first surveys in the Baltic and Caspian seas are described. Finally, special attention is paid to the hydrographical surveys and charting of the Aegean Sea during the Russian‐Turkish war of 1768–1774, the sources and methods involved, and the little‐known Atlas of the Archipelago (1788) which was created from the surveys.  相似文献   
93.
94.
Higher education commentators have become concerned about how learning and teaching praxis across the sector may unwittingly advantage White British (WB) compared to Black and Minority Ethnic (BME) students. Adopting critical race theory, this article explores these issues in relation to field teaching in geography and related subjects. It reports on primary data collected from students about to attend their first residential field trip. The research shows that WB and BME students approach their first field trip with diverse geographical experiences. The findings indicate a need to reflect critically on our fieldwork routines in order to promote inclusivity in field learning.  相似文献   
95.
This study focuses on microinclusions of platinum group minerals (PGMs) in gold objects from the South Urals and North Black Sea archaeological sites. We demonstrate for the first time that melting of gold during archaeometallurgical work affects PGM microinclusions. Desquamation of primary PGM microinclusions with 28–55 wt% Os in the melt and their oxidation by hot air microbubbles results in the formation of secondary particles with 1–20 wt% Os around the primary inclusions. We conclude that the composition only of primary PGM microinclusions in ancient gold products is comparable to the composition of those from natural sources.  相似文献   
96.
In this study, we present a novel, safe method for how to remove inorganic components from soil samples studied for archaeological purposes, in order to improve studies of the distribution of black carbon in the sedimentary record. As the depositional history of this material depends on the interaction between humans and the natural environment, this method can be widely used in archaeology, landscape archaeology, palaeoecology, environmental geology and sedimentology. Our method does not require the use of dangerous hydrofluoric acid, which is commonly used for the removal of silicon oxide from such samples; therefore, this procedure allows even less chemically trained scientists to analyse soil samples with an increased level of work safety.  相似文献   
97.
Michael Ekers  Alex Loftus 《对极》2020,52(1):78-100
This paper develops a genealogy of concrete labour, paying particular attention to debates within marxist, feminist-marxist and Black feminist writings. Our argument pivots around the dual character of (re)productive activities and an argument that the concrete is both an “aspect” of labour and the concentration of many different relations. We begin with a critique of the false universalisms in certain invocations of the concrete, noting how the far right has mobilised this “false concrete” in the figure of the people. Teasing out long-standing debates over the dual character of labour enables us instead to better understand the social differentiation within concrete lived activity. Through discussing the internal relations that constitute the concrete as labour and method we propose a critical strategy that challenges false universalisms, provides a way to understand relationally defined positionalities, and that is also a place from which to struggle and organise.  相似文献   
98.
In 1347 the Black Death was introduced from the north-eastern coast of the Black Sea and the Sea of Asov towards southern and western Europe, where it then spread dramatically. A report by the Italian chronicler Gabriel de Mussis of the siege of Caffa (1345–47) is often credited as describing an early deployment of a “biological weapon”, thus triggering the “Black Death” in western Europe. He reports that Mongol troops threw plague victims into the city with catapults, thus contaminating the inhabitants. However, re-evaluation of historical, biological and epidemiological data indicates that the spread of the disease was probably an inevitable consequence of the intense trade relations along the coasts of the Black Sea and the Mediterranean. Therefore, the alleged catapulting of infected corpses would rather have been a marginal contribution to the diffusion of the disease (if it took place at all). The infection was subsequently spread by refugee ships via ports at Constantinople and along the Mediterranean trading routes and harbours towards Genoa, Marseille and Venice, thus initiating the Plague in Europe. The further propagation of the disease inland is still a matter of controversial discussions. However, epidemiological data indicate that the most essential animal vector for further distribution of the plague in central and northern Europe was probably the human louse (Pediculus humanis), instead of the oriental (or tropical) rat flea (Xenopsylla cheopis).  相似文献   
99.
This article focuses on the reign of James II of Scotland (1437–1460) and argues that the Scottish king deliberately attempted to gain a monopoly over chivalry as part of his assertion of royal power. In seeking to integrate the historiographies of state-building and chivalric culture in fifteenth-century Scotland, what is offered here is an account of the principal strategies employed by James II to establish royal authority throughout Scotland, and an assessment of the various means in which chivalry was being patronised and promoted by the Scottish nobility and the political challenge inherent in this activity. James's response to this challenge is examined through a series of incidents in the 1450s and, in this manner, seeks to rethink the role of chivalry in late medieval Scotland. Far from being a peripheral cultural practice, this article argues that it should be seen as an integral part of James II's state-building agenda.  相似文献   
100.
Carlos Serrano 《对极》2023,55(2):599-619
This article focuses on how educational institutions are crucial sites for understanding how racial capitalism and anti-Black violence are reproduced. Centring Chapel Hill, home of the University of North Carolina (UNC), and its neighbouring town of Carrboro as a university town built by racial capitalist and anti-Black practices, I analyse how the university functions as a social reproductive force that structures the town and its local public education system. Building on my ethnographic research, Black studies literature, and Black geographic thought, I argue that the university partakes in the political, economic, and ideological restructuring of a community that enables hierarchical differences to be produced in schools in terms of how success is rooted with liberal notions of the individual and proximity to whiteness. Paying attention to these relationships challenges us to think about the need for the total eradication of oppression in all forms to truly have liberated educational spaces.  相似文献   
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