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During the two influenza pandemic’s (caused by H1N1 and SARS-Cov-2), over the past twenty years, the use of experimental microwave generated steam (MGS), has shown potential, for decontamination of single-use face respirators and surgical masks. Recent review articles of the decontamination of single-use respirator and face mask has been primarily performed within the health sector, with a particular focus on the disinfection efficiency of the process. However, as with all processing data collected from different research sources, experimental conditions are not reported in a consistent manner. These reports generally provide an overview of MGS microwave conditions with insufficient detail to allow a standard microwave engineering review that enables the thermodynamic of the microwave treatment, to be obtained. The understanding of these parameters and how they influence the decontamination outcome is necessary for further development of the MGS process and enable it to help address some of Green chemistry goals (reduce the amount of harmful chemical products in the environment, and limit the number of respirators and masks required to be manufactured). This review reports on the MGS microwave conditions, then clarifies them in to standard microwave engineering terminology from which the thermodynamic of process can be obtained. In particular how the parameters: power (W), power density (W L-1 ) and process energy budget (J) is reflected in steam generation as well as MGS decontamination of respirator and face mask outcome. The work reviews the treatment of N95-type respirators, surgical and medical masks, and in this context also considers microwave oven-related injuries and mask related fires. Using this knowledge, meaningful recommendations are made on the suitability of individual microwave ovens for decontamination treatment in addition the respirator to the suitability of respirator for use with the MGS decontamination process. Finally, general recommendations are provided for designing a microwave oven for MGS decontamination.

LabVIEW software is used to decode step sequences generated by Irish light and hard shoes and bare feet. To remove the low frequency reverberation of the floor a Savitzky-Golay digital filter is used to de-convolute the percussion sound of the step sequences. Floor types and foot apparel are compared. Deposited by bulk import 1/11/2013. SB.

Plasma treatments are widely used to activate polymer surfaces prior to adhesive bonding. This study investigates the influence of plasma treatment conditions on the surface activation of a range of polymers using the PlasmaTreat (Open Air) system. In this study the effect of dc pulse plasma cycle time, compressed air flow rate and the plasma jet nozzle to substrate distance on the plasma discharge was examined. The influence that the dc pulse plasma cycle time parameter has on the activation of polypropylene, polystyrene and polycarbonate was also investigated. The level of polymer surface activation was evaluated based on the change in water contact angle after plasma treatment. The polymer surface properties were also monitored using AFM and XPS measurements. The heating effect of the plasma was monitored using both infrared thermographic camera and thermocouple measurements. Plasma diagnostics measurements were obtained using the photo-diode and optical emission spectroscopy techniques. From this study it was concluded that for the PlasmaTreat system the level of plasma activation was closely correlated with the dc pulsed plasma cycle time, which is a measure of the plasma intensity. For example, the more intense plasma obtained with shorter cycle times gave higher levels of polymer activation. The optimized pulsed plasma cycle times were found to be specific for a given polymer type and related to their thermal properties. The pulsed cycle times were also found to correlate with both the substrate and plasma gas temperatures. Author has checked copyright AMS