The pressure wire has emerged as a useful tool to assess the clinical severity of moderate coronary artery lesions. We report a novel use of the pressure wire in adult patients with complex congenital cardiac disease in whom it was used in assessing pressures beyond the stenosis in the distal pulmonary artery, aorto-pulmonary collaterals, and across prosthetic tricuspid valves, where conventional catheters were unable to reach. We used this in three of our patients for assessment of pulmonary artery pressures and in two patients for assessment of pressures across a prosthetic St Jude® valve. Out of the three patients referred for assessment, only two had significantly raised distal pulmonary pressures enabling them to receive appropriate therapy. Out of the two patients with a prosthetic tricuspid valve, only one required surgery based on this assessment. We describe a novel use of the pressure wire in the functional assessment of adults with congenital cardiac disease in whom conventional catheter techniques may not be able to provide adequate data. It can be a guide to provide appropriate therapy and avoid unnecessary interventions in this patient group.

In the present work, an experimental study on how to increase the heat transfer coefficient (HTC) in double pipe heat exchanger (DPHE) use of a variety of Al2O3 Nano-dispersion concentrations mixed in water as base fluid with air bubble injection for counter flow arrangement under turbulent flow conditions with (Re) Reynold number range from (6000 t0 45000) . The thermal performance of (DPHE) has been enhanced with the use of two techniques. The first, is represented by adding nanoparticles to hot water (inner pipe) raising the (HTC) inside the inner tube. Increase the volume concentration cause increase in the viscosity of the nanofluid leading to increase in friction factor .Secondly is represented by Air bubble injection in outer pipe with cold water to enhance the (HTC). The mobility of air bubbles inside the water from down to up by the force of the buoyancy, and the movement of these air bubbles results in significant mixture and turbulence within the water. The variations of number of thermal units (NTU), exergy loss, dimensionless exergy and (Nu) are evaluated. The investigated parameters were cold water volume flow rates (8, 10, 12 and14) l/min, flow in outer tube. Also, three different volume flow rates of air (12, 16 and 20) l/min mixed with water in outer tube. The volume flow rates of hot water remains constant at (8 l/min) flow in inner pipe with three volumetric concentrations of given nanofluid. The results showed that the air bubble injection throughout the tube gave maximum enhancement in heat transfer characteristics followed by the no air bubble injection. Since the enhancement in heat transfer characteristics varies linearly with the volumetric concentration of Nanofluids, Nanofluids with 0.3% of Al2O3 nanoparticles gave more enhancements in (HTC) than the case without nanofluid. The Nusselt number increased about (8% - 45%).

The fatigue limit and lifetime of epoxy-based coatings may be affected by various factors, especially the environmental effects. This paper evaluates the impact of air, potable water media, and pollution gases (CO2, H2S, and SO2) on the fatigue performance of two types of epoxy-based coatings (polyamine and polyamide epoxy-based coatings) used as lining for potable water storage tanks. The fatigue test apparatus is assembled in the laboratory and utilized for testing. Different factors are discussed, including absorption, adsorption, and the reaction of environmental gasses with polyamine and polyamide coating surfaces. The influence of porosity on the epoxy-based coatings is experimentally determined, and its effects on fatigue limit and fatigue life are discussed in detail. As a result, the coatings were applied to improve the fatigue resistance of stainless steel. The fatigue limits of both types of coatings tested in potable water are lower than the value obtained when tested in air or gas environments. The fatigue limit of polyamine coating is greater than the polyamide coating. The microscopic inspection indicated a different mechanism for initiating fatigue crack, and the test environments are affected by the nature of the fracture surface.