223 research outputs found

    The examination of archaeometallurgical remains; some recent examples and conclusions

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    This paper starts with a description of the investigational techniques now being used and goes on to discuss some of the problems and results. Examples have been taken from such finds as mattes and slags, litharge and speiss, native copper and crucible melting, edge tools, copper and bronze ingots, and oxidation enrichment in wrought iron

    Iron oxidation at low temperature (260–500 C) in air and the effect of water vapor

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    The oxidation of iron has been studied at low temperatures (between 260 and 500 C) in dry air or air with 2 vol% H2O, in the framework of research on dry corrosion of nuclear waste containers during long-term interim storage. Pure iron is regarded as a model material for low-alloyed steel. Oxidation tests were performed in a thermobalance (up to 250 h) or in a laboratory furnace (up to 1000 h). The oxide scales formed were characterized using SEM-EDX, TEM, XRD, SIMS and EBSD techniques. The parabolic rate constants deduced from microbalance experiments were found to be in good agreement with the few existing values of the literature. The presence of water vapor in air was found to strongly influence the transitory stages of the kinetics. The entire structure of the oxide scale was composed of an internal duplex magnetite scale made of columnar grains and an external hematite scale made of equiaxed grains. 18O tracer experiments performed at 400 C allowed to propose a growth mechanism of the scale

    Do the type and number of blockholders influence R&D investments? : new evidence from Spain

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    Using data from 3,638 Spanish firms between 1996 and 2000, this article studies the relationship between the presence of large shareholders in the ownership structure of firms and R&D investment. Consistent with our theoretical contention, our results indicate that the impact of large shareholders on the R&D investment is (1) negative when blockholders are banks, (2) positive when blockholders are non-financial corporations and (3) null when blockholders are individuals. In addition, we find a systematic negative relationship between the number of blockholders and R&D investment. Finally, we extend our study by analysing the influence that the combined effect between blockholder type and R&D investment has on the firm’s economic performance. Results of this work provide relevant implications for policy makers and academic research.Publicad

    The impact of the Great Exhibition of 1851 on the development of technical education during the second half of the nineteenth century

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    This paper examines the contribution made by the mechanics’ institute movement in Britain just prior to, and following, the opening of the Great Exhibition of 1851 in London. It argues that far from making little contribution to education, as often portrayed by historians, the movement was ideally positioned to respond to the findings of the Exhibition, which were that foreign goods on display were often more advanced than those produced in Britain. The paper highlights, through a regional study, how well suited mechanics’ institutes were in organising their own exhibitions, providing the idea of this first international exhibition. Subsequently, many offered nationally recognised technical subject examinations through relevant education as well as informing government commissions, prior to the passing of the Technical Instruction Acts in 1889 and the Local Taxation Act of 1890. These acts effectively put mechanics’ institutes into state ownership as the first step in developing further education for all in Britai

    Network capitalism and the role of strategy, contracts and performance expectations for Asia-Pacific innovation partnerships

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    © Springer Nature Singapore Pte Ltd. 2018. With the growth of emerging economies in Asia-Pacific over the last three decades collaboration with the aim of innovation between firms within and with partners outside the region have developed substantially. Not always have such partnerships fulfilled their anticipated strategic objectives. The literature suggests that the nature of market arrangements and the role of government within that system play a role, but also innate contracting practices and governance of innovation partnerships are related. Yet, our understanding about the specific relationships between these factors and the emerging partnership innovation culture that facilitates joint business activities in an Asia-Pacific context remains vague. In this conceptual chapter we suggest how characteristics of so called network capitalism in conjunction with the nature of contractual agreements between partners, the alignment of their innovation objectives and the ambiguity inherent in their mutual contributions to the partnership can be interpreted as indicators of joint innovation culture. However, while innovation partnerships generally may result to be bureaucratic, market, clan, or adhocracy, we discuss how in an Asia Pacific context, innovation partnerships are limited by the extent of codification and diffusion of information and the social embeddedness of economic transactions

    Identifying evidence for past mining and metallurgy from a record of metal contamination preserved in an ombrotrophic mire near Leadhills, SW Scotland, UK

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    This study presents a new 3600-year record of past metal contamination from a bog located close to the Leadhills and Wanlockhead orefield of southwest Scotland. A peat core, collected from Toddle Moss, was radiocarbon (14C) dated and analysed for trace metal concentrations (by EMMA) and lead isotopes (by ICP-MS) to reconstruct the atmospheric deposition history of trace metal contamination, in particular, lead. The results show good agreement with documented historical and archaeological records of mining and metallurgy in the region: the peak in metal mining during the 18th century, the decline of lead mining during the Anglo-Scottish war and lead smelting during the early medieval period. There may also have been earlier workings during the Late Bronze and Iron Ages indicated by slight increases in lead concentrations, the Pb/Ti ratio and a shift in 206Pb/207Pb ratios, which compare favourably to the signatures of a galena ore from Leadhills and Wanlockhead. In contrast to other records across Europe, no sizeable lead enrichment was recorded during the Roman Iron Age, suggesting that the orefield was not a significant part of the Roman lead extraction industry in Britain. These findings add to the various strands of archaeological evidence that hint at an early lead extraction and metallurgical industry based in southern Scotland. The results also provide further evidence for specific regional variations in the evolution of mining and metallurgy and an associated contamination signal during prehistoric and Roman times across Europe
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