5 research outputs found

    Microwave plasma chemical vapour deposition diamond nucleation on ferrous substrates with Ti and Cr interlayers

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    Diamond-coated steel is considered an important issue in synthetic diamond technology due to the great economical importance of enhancing the wear resistance and surface hardness of commercial Fe-based alloys. However, direct diamond coating by chemical vapour deposition (CVD) is rather problematic-adhesion and growth are seriously affected. The use of interlayers is a common approach to minimise these problems. This work reports an investigation on the establishment of good nucleation and growth conditions of diamond films by microwave plasma CVD (MPCVD) on ferrous substrates coated with Ti and Cr interlayers. Commercial grade ferrous substrates were pre-coated with commercial interlayers by sputtering (Ti, Cr) and electroplating (Cr) techniques. Steel substrates led to better results than iron cast substrates. The best films were obtained on Ti pre-coated steel substrate. The results on Cr interlayers pointed to the advantage of electroplating over the physical vapour deposition (PVD) sputtering. From the two selected parameter sets for diamond deposition, the one using lower power level conducted to the best results. Initial roughness and growth parameters were found to counteract on the uniformity of the diamond films. The morphology was studied by scanning electron microscopy (SEM), the roughness was estimated by profilometry, while diamond quality and stress state were evaluated by mu-Raman spectroscopy. (C) 2002 Elsevier Science B.V. All rights reserved

    Workloads, strain processes and sickness absenteeism in nursing

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    OBJECTIVE: to analyze the workloads, strain processes and sickness absenteeism among nursing workers from a teaching hospital in the Brazilian Central-West. METHOD: a descriptive and cross-sectional study was developed with a quantitative approach, based on the theoretical framework of the social determination of the health-disease process. Data were collected between January and December 2009, based on records of complaints related to occupational exposure among nursing professionals, filed in the software Monitoring System of Nursing Workers' Health. For the sake of statistical analysis, relative and absolute frequencies of the variables and the risk coefficient were considered. RESULTS: 144 notifications of occupational exposure were registered across the analysis period, which represented 25% of the total nursing population at the hospital. The physiological and psychic workloads were the most representative, corresponding to 37% and 36%, respectively. These notifications culminated in 1567 days of absenteeism for disease treatment. CONCLUSIONS: the findings evidence the impact of occupational illnesses on the absenteeism of nursing workers, and can be used to demonstrate the importance of institutional investments in occupational health surveillance
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