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对纳米NiAl样品进行电子自旋共振（ESR）研究时发现晶粒尺寸效应产生的非磁-磁性转变．大块多晶NiAl合金的没有ESR信号，只有很弱的Pauli顺磁性．而粒径为8．6nm的纳米NiAl样品的ESR信号，随温度的增高而显著下降，其居里温度Tc为124K，在室温下ESR信号很弱．8．6nm的纳米NiAl样品经550℃和707℃退火处理后得到粒径分别为12nm和21nm的两个样品，它们在室温下都有较强的ESR信号，并能够被永磁体吸起。多晶NiAl合金与纳米NiAl之间存在非磁-磁性转变，
Electron spin resonance (ESR) studies on nano-NiAl samples revealed nonmagnetic-magnetic transitions caused by grain size effects. Large polycrystalline NiAl alloy no ESR signal, only weak Pauli paramagnetic. However, the ESR signal of nano-NiAl particles with a size of 8.6 nm decreased significantly with increasing temperature, and the Curie temperature Tc was 124K. The ESR signal was weak at room temperature. After annealed at 550 ℃ and 707 ℃ for two samples of 8.6nm nano NiAl, two samples with diameters of 12nm and 21nm were obtained. They all have strong ESR signal at room temperature and can be attracted by the permanent magnet. There is a non-magnetic-magnetic transition between polycrystalline NiAl alloy and nano-NiAl,