For transformer cooling applications, magnetic particles need to be dispersed in carrier fluids with high colloidal stability for a long period without significant degradation. However, stability of the suspension, especially the long term colloidal stability is a crucial factor for the applications in power transformers because aggregation of particles could cause clogging of micro-channels in transformers. In this article, we have reported effect of hydrodynamic size on the colloidal stability of Mn1-xZnxFe2O4 (MZ) nanoparticles (NPs)–based magnetic fluids. Lifetime of fluids has been determined from the increase in hydrodynamic size of magnetic NPs due to aggregation. Colloidal stability of fluids decreases with increase in the polydispersity of fluids caused by the enhanced dipole interactions between NPs resulting in the aggregation of NPs in chain-like structures. Abstract Graphic Chain formation in magnetic nanoparticles in fluids due to aging Chain formation in magnetic nanoparticles in fluids due to aging

中文翻译：

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流体力学尺寸对Mn-Zn磁性流体胶体稳定性和寿命的影响

对于变压器冷却应用，磁性颗粒需要长时间分散在具有高胶体稳定性的载液中而不会显着降解。然而，悬浮液的稳定性，尤其是长期胶体稳定性是电力变压器应用的关键因素，因为颗粒的聚集会导致变压器中的微通道堵塞。在本文中，我们报道了流体力学尺寸对 Mn1-xZnxFe2O4 (MZ) 纳米粒子 (NPs) 基磁性流体胶体稳定性的影响。由于聚集，磁性纳米颗粒的流体动力学尺寸的增加已确定流体的寿命。流体的胶体稳定性随着流体多分散性的增加而降低，这是由于 NPs 之间增强的偶极相互作用导致 NPs 在链状结构中聚集。摘要 由于老化导致流体中磁性纳米颗粒的链形成 由于老化导致流体中磁性纳米颗粒的链形成