The thermomechanical properties of polyurethane shape memory polymer (SMP) foams were investigated experimentally. The results obtained can be summarized as follows. (1) By cooling the foam after compressive deformation at high temperature, stress decreases and the deformed shape is Ž xed. Stress decreases markedly in the region of temperature below the glass transition temperature Tg during th...

The hot deformation of TA15 titanium alloy was studied by the compression test on Gleeble-3800 thermal simulation equipment. true stress-strain curves at temperature 1123-1223K and strain rate 0.001-1s -1 were obtained.. results show that flow stress increases with decreasing temperature, as increases. And process is accompanied work hardening dynamic recovery recrystallization. Based alloy, Ar...

We have characterized a nonlethal selection for mutations that allow Escherichia coli to grow on large maltodextrins (Dex+) in the absence of the lamB encoded maltoporin LamB. These Dex+ mutations occur before and after imposition of the selection and the selection does not result in a general increase in mutagenesis. The recovered Dex+ mutations are almost exclusively mutations that alter the ...

In this study, in order to obtain a functionally graded material, NiTi strips were annealed at 350°C, 450°C and 550°C in a furnace using an assembly that allowed a temperature gradient along them, and their transformation temperatures were studied by Differential Scanning Calorimetry (DSC). Furthermore, the strips were bent at both ends and dipped into a water bath at room temperature which was...

AIMS To determine the feasibility of strain rate imaging (SRI) in the objective detection of exercise-induced ischaemia. METHODS AND RESULTS Sixteen patients undergoing elective percutaneous coronary intervention (PCI) underwent treadmill exercise stress echocardiography (ESE) pre- and post-PCI. Measurement of systolic SRI parameters was attempted in all myocardial segments at baseline, peak ...