The axial modulus ESMA(κ) of FeMnSi-based shape memory alloys (FeMnSi-SMAs) is a parameter introduced in this study to characterize the relationship between stress and strain behavior at the early stage of tensile loading. ESMA(κ) can be used to correctly estimate and model the interaction forces between FeMnSi-SMAs and other materials. Unlike the conventional Young’s modulus, which is usually given at room temperature, the ESMA(κ) is evaluated at different temperatures and strongly depends on phase transformation and plastic deformation. This study investigated the evolution of ESMA(κ) during and after pre-straining as well as in the course of the activation processes. The effect of different factors (e.g., phase transformation and plastic deformation) on the magnitude of ESMA(κ) is discussed. The result shows that the ESMA(κ) can differ significantly during activation and thus needs to be modified when interaction forces between FeMnSi-SMAs and other substrates materials (e.g., concrete) must be modeled and evaluated.

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In this paper, we prepared a novel double-layer Perilla essential oil composite membrane microcapsule (PEOCM) by the composite methods of complex coacervation and interface polymerization. The particle size distribution, morphology, pressure resistance, thermal stability, and elemental proportions of the microcapsule shell of the obtained microcapsules were characterized by laser particle size analyzer, scanning electron microscopy (SEM), dynamic rheometer, thermogravimetric analysis (TGA), and energy spectrometer. In order to further examine the application effect of the PEOCM, we carried out a fresh-keeping experiment on nectarines. The results showed that the average volume diameter of the microcapsules was 226.9 µm, with a completely spherical shape and a slight depression on the surface and had good pressure resistance and thermal stability. The results also demonstrated that microencapsulation does not change the composition of Perilla essential oil, and the polyurea membrane with amide structure (-NH-CO-NH-) was formed successfully. Furthermore, the total soluble solids content and peroxidase activity of nectarines indicated that the PEOCM can be a preservative of food.

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