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The hydrodynamics of the G1 fluidic module of the Corning Advanced-Flow reactor (AFR) was characterized using particle image velocimetry. Two series of experiments, single-phase flow with liquid flow rates of 10–40 mL/min and two-phase flow with an identical overall flow rate range and gas volume transport fractions ranging from 0.125 to 0.50, were performed. From the instantaneous velocity vector maps, the mean and the root-mean-square velocities were computed, which allowed a systematic investigation of the single- and two-phase flow hydrodynamics and transport processes in the AFR. In single-phase flow, the velocity field is symmetric in the heart-shaped cells, and their particular design results in a stagnation zone that limits momentum exchange in each cell. The addition of the gas phase greatly increases the momentum exchange in the heart-shaped cells, which leads to a more uniform distribution of velocity fluctuations and increased transport processes within the AFR.

This paper was presented at the 4th Micro and Nano Flows Conference (MNF2014), which was held at University College, London, UK. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute, ASME Press, LCN London Centre for Nanotechnology, UCL University College London, UCL Engineering, the International NanoScience Community, www.nanopaprika.eu. In the present work, gas–liquid hydrodynamics and mass transfer in horizontal circular capillaries of different diameters are investigated experimentally. The capillary diameters range from 0.5 to 3.2 mm in order to investigate the mass transfer process on both micro and milli scale. The mass transfer is studied using the chemical absorption of CO2 into an alkaline solution. A high speed camera is used to capture images of the flow. Subsequently, the images are analysed thought a specifically developed Matlab code. Such a code is able to extract important hydrodynamic parameters (bubble length, liquid slug length, void fraction, film thickness, bubble velocity etc.) that affect the mass transfer coefficient, kLa. The obtained results both for the hydrodynamics of the flow and for the mass transfer are compared with those present in literature, and the scalability of the mass transfer coefficient is assessed.

The increased and irregular post-maximal deflection of the two limbs of thromboelastographic traces has been variably interpreted by the Authors who utilize TEG as a global screening test for haemostasis evaluation. These thromboelastographic patterns have been attributed either to enhanced fibrinolytic activity or to raised clot's rectractility or even to incorrect technique. In our study, 1701 TEG's traces carried out in the last five years have been reviewed in order to evaluate the incidence of such patterns in both healthy subjects and in patients affected by different diseases. The data obtained show that such irregular post-maximal deflection's patterns are quite absence in healthy subjects while reaches a statistically significant incidence only in patients affected by diabetes mellitus, obesity or systemic hypertension. The results seem to suggest that the increased and irregular post-maximal TEG deflection is not a simply product of technique's mistake but may represent an useful index of some haemostatic alterations which need further studies.

This work addresses the experimental study of a new systematic series of stepped planing hulls. Indeed, the interest in the stepped planing hulls is constantly growing, both in the industrial/commercial and academic fields. Designers and boat builders have been orienting toward the multi-stepped hulls solution to ensure good dynamic stability, reliable seakeeping and operability at high speeds. However, there is a lack of a compre hensive stepped hull systematic series with various step configurations including a forward V-shaped step, as typically used on modern boats. For the abovementioned reasons, a systematic series of eight different models of stepped hulls have been developed and tested. The towing tank tests have been carried out at the naval basin of the Universita ` degli Studi di Napoli “Federico II” Dipartimento di Ingegneria Industriale (DII) in calm water at different speeds (Fr∇ = 1.077–6.774) and for three different static trim conditions. All models are built with a transparent bottom to visualize the wetted surface and the eventual development of vortices generated behind the step. The eight models are defined by modifying three significant design parameters for stepped hulls (i.e. the number of steps, longitudinal step position, and step height).