197 research outputs found

    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

    The Budget Constraint in the Governance of Organizations

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    The paper suggests a partial solution to the disjunction between the institutional environment and the institutions of governance by considering the budget constraint. This approach is put in the perspective of the comparative analysis of economic organizations as discrete structural alternatives. The budget constraint presents a whole range of alternative values that are distinct by different transaction costs that organizations meet. Following different values of budget constraint, bounded rationality and opportunism are allocated to alternative uses and asset specificity takes different forms. This approach requires that the discriminating alignment solution considers the prevailing value of the budget constraint, which opens the need for a comparative perspective on efficacious organizational governance. A second level of governance is corporate governance. The debate over corporate governance is centered around decision-making power and the existence of quasi-rents that organizations produce. Given different values of the budget constraint, the definition of what are efficacious systems of decision-making power and appropriation of quasi-rents are distinct in the shareholder value and the stakeholder interest paradigms

    La explotación tartésica de la casiterita entre los ríos Tajo y Guadiana: San Cristóbal de Logrosán (Cáceres)

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    The objective of this work is to offer a synthesis of the archaeological and archaeo-mining investigation carried out in recent years (1998 and 2000-2002) in the Cerro de San Cristobal site, Logrosán (Cáceres). The results allow us to propose a chaîne opératoire for the cassiterite treatment and use in Cerro de San Cristóbal during the transition from the Late Bronze Age to the Orientalizing period. The management and role of this mineral in the Tajo-Guadiana relations and in the Atlantic- Mediterranean circuits meeting in the Southwest of the Iberian Peninsula, together with other factors, seems to justify the early integration of the territory of Extremadura in Tartessos. The investigation in Logrosán and the archaeology of tin were suddenly interrupted by the unexpected death of its main promoter, Dr. Craig Merideth. The continuation of this project is now to be channelled through the recent declaration of the Cerro de San Cristobal as a ‘geosite’ in the ‘Ibores-Villuercas- Jara Geopark’ and through the National Research, Development and Innovation Scheme’s project <i>El tiempo del tesoro de Aliseda</i>, among whose actions is the archaeomining survey from the West of the peneplain of Cáceres made in 2011.<br><br>El objetivo de este trabajo es ofrecer una síntesis de la investigación arqueológica y arqueominera realizada entre 1998 y 2000-2002 en el Cerro de San Cristóbal de Logrosán (Cáceres). Esta permite proponer una probable ‘cadena operativa’ del beneficio de la casiterita en este lugar durante el tránsito Bronce Final-Periodo Orientalizante. La gestión e imbricación del mineral en las relaciones Tajo-Guadiana y en los circuitos atlántico-mediterráneos confluyentes en el Suroeste de la Península Ibérica parecen justificar, entre otras razones, la temprana integración del actual territorio extremeño en Tartessos. La investigación en Logrosán y la arqueología del estaño se vieron bruscamente interrumpidas por el inesperado fallecimiento de su principal impulsor, Craig Merideth. Su continuidad pretende canalizarse a través de la reciente declaración del Cerro de San Cristóbal como “geositio” del Geoparque “Ibores-Villuercas-Jara” y del proyecto del Plan Nacional I+D+i <i>El tiempo del tesoro de Aliseda</i>, entre cuyas acciones se encuentra la prospección arqueominera del oeste de la penillanura cacereña realizada en 2011
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