The effect of acetylation on the physicochemical properties of chickpea starch was studied. After the chickpea starch was acetylated, the basic properties were measured. When the degree of substitution (DS) was 0.1004 and the temperature was 95 °C, the solubility and swelling power of starch were 19.6% and 21.4 g/g, respectively. The freeze–thaw stability of acetylated starch paste increased with the increase in the degree of substitution. The surface morphology of starch granules changed, but the crystalline morphology did not change, and the C-type crystalline structure was still maintained. There are three new absorption peaks in the infrared spectroscopy of starch, and the -COCH3 group was introduced. With the increase in DS, the viscosity of esterified chickpea starch decreased gradually. Compared with unmodified chickpea starch, the ability to form gel was poor.

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Spin current, the flow of spin angular momentum, can carry and transport energy and/or information without generating Joule heating, which makes spin-based devices expected to be one of the potential aspects for the next generation information processing devices. It is important to investigate the generation, transport, and detection of spins for the development of spin-based devices, in which the spin transport and its related phenomena attract ongoing interests due to the complex interactions between spins and condensed matter systems. Here, spin transport phenomenon is studied at a heterojunction consisting of ferromagnetic metal nickel and nonmagnetic heavy metal platinum, where transport spins are found to be totally blocked. Two series of spin-pumping devices were made in this work which were the yttrium iron garnet (YIG)/Ni/Pt trilayer devices and the contrastive YIG/Ni bilayer devices. YIG was employed as the substrate and the spin-pump layer, on which nickel and platinum films were deposited by dc magnetron sputtering system. Spin currents were generated from YIG and injected into nickel layers by spin pumping technology. Voltage signals corresponding to the inverse spin Hall effect were detected and analyzed comparably for both YIG/Ni/Pt trilayer and YIG/Ni bilayer devices. It is found that the platinum layers in YIG/Ni/Pt trilayer devices only play as charge current shunting but do not contribute to the spin-charge conversion. This implies that the spin current can not transport through the Ni/Pt interface even when the nickel layer is as thin as 1 nm, which means in other words that the spin current is blocked at the Ni/Pt interface. Our result proposes a heterojunction that can block transport spins totally has never been discussed before, which may expand the views and trigger new functions for the development of spin-based devices.

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