论文标题
磁凝聚和相关的高温性能的纳米颗粒尺寸阈值
Nanoparticle size threshold for magnetic agglomeration and associated hyperthermia performance
论文作者
论文摘要
磁性纳米颗粒与凝聚的可能性通常是通过磁性偶极 - 偶极和热能之间的比率来估计的，因此忽略了这样一个事实，即，根据磁各向异性常数（$ K $）的大小，粒子矩可能会内部波动，从而破坏了凝集过程。基于相关时间尺度之间的比较，我们在这项工作中研究了磁凝聚的阈值大小（$ d_ {gggl} $）如何取决于$ k $值。我们的结果表明，$ k $ - 形状贡献 - 可能会将$ d_ {aggl} $换成几个nm。提供了与通常的\ textit {superparamagnetism}估计以及能量竞争方法的比较。此外，基于各向异性在高温性能中的关键作用，我们还分析了相关的加热能力，因为非凝聚的颗粒对于应用而言是很高的关注。
The likelihood of magnetic nanoparticles to agglomerate is usually estimated through the ratio between magnetic dipole-dipole and thermal energies, thus neglecting the fact that, depending on the magnitude of the magnetic anisotropy constant ($K$), the particle moment may fluctuate internally and thus undermine the agglomeration process. Based on the comparison between the involved timescales, we study in this work how the threshold size for magnetic agglomeration ($d_{aggl}$) varies depending on the $K$ value. Our results suggest that small variations in $K$ -due to e.g. shape contribution-, might shift $d_{aggl}$ by a few nm. A comparison with the usual \textit{superparamagnetism} estimation is provided, as well as with the energy competition approach. In addition, based on the key role of the anisotropy in the hyperthermia performance, we also analyse the associated heating capability, as non-agglomerated particles would be of high interest for the application.
