Two-layer laser clad coating as a replacement for chrome electroplating on forged steel

Chrome plating is one of many surface engineering techniques used for corrosion resistance, as well as a protective coating against surface damage in load bearing applications, with surface hardness in the region of 1000Hv. Laser cladding is an alternative hardfacing technique often chosen for corrosion resistance and for increasing the surface hardness of components, through thick clad coatings. The application of chrome plating and other similar surface engineering techniques for thick coatings can be inefficient and costly with practical process limitations. The objective of this case study was to investigate the feasibility of replacing the chrome plated layer of a rod mill pinion, made of forged steel, with a Nickel-based Tungsten-Carbide (Ni-WC) composite layer and an intermediate layer of Inconel 625. Mechanical properties were obtained using microhardness and nanoindentation techniques. Three-point bend tests were performed on test specimens from a pinion sample, in order to observe crack propagation resistance, a challenging task due to the curved geometry of the pinion sample and the difference in thickness between the existing and proposed coating layers. Crack development was captured, and plastic deformation was quantified with the use of Digital Image Correlation (DIC). In bending it was found that the bond between the composite coating, Inconel 625 and the steel substrate provided improved resistance to axial crack propagation, where the composite coating could withstand more than twice the bending tool displacement than the chrome electroplating

Inter-laboratory evaluation, development and validation of fungal preservation regimes used in different European biological resources centres (BRCs)

Successful preservation of fungi relies on the application of optimised preservation protocols that do not compromise the genomic integrity of the organism. Most major European BRCs use lyophilisation and cryopreservation as the methods of choice. Although based on generic principals, protocols can vary between institutions and do not always result in successful recovery. In order to evaluate the efficacy of the methods, a range of fungal strains were circulated around partner collections in the EMbaRC project and the organisms preserved using the standard methods used in each collection. The effectiveness of preservation was assessed using a series of techniques including DNA fingerprinting and sequencing, analysis of culture characteristics, viability assessments and the use of MALDI-TOF. The results showed that when viable cultures were obtained after preservation, they appeared to retain their genomic integrity, but there was evidence of delayed growth and attenuation in some cultures. Not all fungi were successfully preserved by all methods. It was found that a cryopreservation protocol used by the MUCL collection in Belgium, that limited manipulation of the fungus before preservation, was particularly effective in preserving some of the more delicate fungi and this method is being evaluated by the project partners. A further investigation was undertaken to assess the integrity of four specific strains of fungi deposited in different collections. They were compared using culture analysis, sequence analysis, DNA fingerprinting and MALDI-TOF. It was found that some limited variation was observed at the phenotypic level from the analysis of culture characteristics, but this could be expected, especially in organisms such as Aspergillus which can be prone to strain drift. More importantly, molecular integrity remained consistent with no significant differences observed between lines of the same strain. Therefore, despite the strains having been maintained by different methods over the intervening years from their initial deposit, the collections had maintained them in a stable manner. This is indicative of the benefits of applying proven regimes, resulting in high quality operations

Non-heat related impacts of climate change on working populations

Environmental and social changes associated with climate change are likely to have impacts on the well-being, health, and productivity of many working populations across the globe. The ramifications of climate change for working populations are not restricted to increases in heat exposure. Other significant risks to worker health (including physical hazards from extreme weather events, infectious diseases, under-nutrition, and mental stresses) may be amplified by future climate change, and these may have substantial impacts at all scales of economic activity. Some of these risks are difficult to quantify, but pose a substantial threat to the viability and sustainability of some working populations. These impacts may occur in both developed and developing countries, although the latter category is likely to bear the heaviest burden

Práticas de regulação das aprendizagens de estagiários do 1º ciclo do ensino básico de Portugal

O estudo sobre as práticas de regulação das aprendizagens de estagiários do 1º ciclo do ensino básico permitiu-nos concluir que, resultante da prática da avaliação formativa contínua, a regulação incide, sobretudo, nas dificuldades de aprendizagem dos alunos. Utilizam estratégias de regulação corretivas, mas também, de regulação interativa. Mais condicionadas foram as estratégias de regulação dos diferentes ritmos de trabalho e de aprendizagem dos alunos

Les ruptures d'illusion dans les comédies antiques

info:eu-repo/semantics/publishedMélanges Henri Grégoire, vol. I

Une analyse hiérarchique de la coordination des déplacements chez des enfants préopératoires

info:eu-repo/semantics/publishe