Large magnetic-field-induced strains have been observed in Heusler alloys with a body-centred cubic ordered structure and have been explained by the rearrangement of martensite structural variants due to an external magnetic field. These materials have attracted considerable attention as potential magnetic actuator materials. Here we report the magnetic-field-induced shape recovery of a compressively deformed NiCoMnIn alloy. Stresses of over 100 MPa are generated in the material on the application of a magnetic field of 70 kOe; such stress levels are approximately 50 times larger than that generated in a previous ferromagnetic shape-memory alloy. We observed 3 per cent deformation and almost full recovery of the original shape of the alloy. We attribute this deformation behaviour to a reverse transformation from the antiferromagnetic (or paramagnetic) martensitic to the ferromagnetic parent phase at 298 K in the Ni45Co5Mn36.7In13.3 single crystal.

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Shape memory and magnetic properties of a Ni43Co7Mn39Sn11 Heusler polycrystalline alloy were investigated by differential scanning calorimetry, the sample extraction method, and the three-terminal capacitance method. A unique martensitic transformation from the ferromagnetic parent phase to the antiferromagneticlike martensite phase was detected and magnetic-field-induced “reverse” transition was confirmed in a high magnetic field. In addition, a large magnetic-field-induced shape recovery strain of about 1.0% was observed to accompany reverse martensitic transformation, and the metamagnetic shape memory effect, which was firstly reported in a Ni45Co5Mn36.7In13.3 Heusler single crystal, was confirmed in a polycrystalline specimen.

Internal friction and modulus changes associated with martensitic and reverse transformations in a single crystal Magnetic and martensitic transition behaviors of a Ni 46 Mn 41 In 13 Heusler alloy were investigated by differential scanning calorimetry and vibrating sample magnetometry. A unique martensitic transition from the ferromagnetic austenite phase to the antiferromagneticlike martensite phase was detected and magnetic-field-induced "reverse" transition was confirmed in a high magnetic field. In addition, a large positive magnetic entropy change, which reached 13 J / kg K at 9 T, was observed to accompany reverse martensitic transition. This alloy shows promise as a metamagnetic shape memory alloy with magnetic-field-induced shape memory effect and as a magnetocaloric material.

Hot air and vacuum drying were performed to investigate changes in the moisture content, hardness, L-ascorbic acid content, antioxidant activity, and surface color of kiwifruit samples over the course of the drying process at temperatures of 50, 60, and 70°C and a vacuum drying pressure of 3.00 kPa. The residual ratio of AsA and the antioxidant activity in the dried kiwifruit samples was 0.75-0.99 and 4.3-5.5, respectively. The L-ascorbic acid changes in the kiwifruit samples during the hot air drying process followed first order reaction kinetics. Changes in the sample hardness and antioxidant activity were represented by zero-order reaction kinetics. The sample surface color changes after drying were also measured, and the total color change (E) of the samples at all temperatures and for each drying process was greater than 12. The sample color changes (a*) after vacuum drying at each temperature level were significantly (P < 0.01) lower than those associated with hot air drying.