文档介绍：微纳米颗粒悬浮液的制备与表征中文摘要 I 微纳米颗粒悬浮液的制备与表征中文摘要近年来,纳米锶铁氧体因其独特的磁性质,受到了人们的广泛关注。本论文系统地研究了锶铁氧体颗粒的制备及其应用,具体研究内容如下: (1)以FeC1 3·6H 2O和SrC1 2·6H 2O为原料,NaOH为共沉淀剂,采用共沉淀法首先制备了前驱体,然后使用熔盐法辅助高温煅烧制备了SrFe 12O 19颗粒。主要探讨了煅烧温度对产物尺寸、形貌和磁性质的影响。实验结果表明,在850 °C煅烧2 h制备的产物具有规则的六角形貌,颗粒尺寸约为110 nm,。(2)以Fe(NO 3) 3·9H 2O和Sr(NO 3) 2为原料,NaOH为共沉淀剂,采用EG辅助水热法制备了SrFe 12O 19纳米粒子。探讨了反应温度、EG用量对产物相组成、尺寸、形貌及磁性质的影响。当EG/去离子水比例为1/1,反应温度为140 °C时,反应24 h制备得到粒径约为25 nm的SrFe 12O 19粒子。使用表面活性剂对SrFe 12O 19进行表面修饰,修饰后的SrFe 12O 19均匀分散到导热油中得到高浓度的导热油基磁性流体。分别使用古埃磁天平和HAAKE流变仪表征了其磁性质、稳定性和流变性质。而且,该磁性流体在交变磁场中有明显的热效应,具有用于肿瘤细胞热疗的潜能。(3)本文中采用三辊研磨机制备了以表面修饰的铁粉为磁性分散相,共沉淀法制备的 SrFe 12O 19纳米粒子作为添加剂的导热油基磁流变液,分析了其沉降稳定性,并使用 HAAKE流变仪和毛细管流变仪研究了其流变性质。考察了磁性颗粒用量、锶铁氧体用量、温度、磁场强度等对磁流变液沉降稳定性和流变性能的影响。同时,使用 Herschel-Bulkley(H-B)模型描述了磁流变液的流变性质。关键词:锶铁氧体、磁性流体、磁流变液、流变性质作者:唐霞指导老师:洪若瑜 Abstract Preparation and characterization of the suspensions of micro/nano-particles II Preparation and characterizationof the suspensions of micro/nano-particles Abstract In resent years, strontium ferrites have obtained extensive attentions due to their unique ic this paper, the preparation, characterization and application of SrFe 12O 19 nanoparticles are investigated. (1) The hydroxide precursors were prepared by co-precipitation using FeC1 3·6H 2O, SrC1 2·6H 2O as the starting materials and NaOH as precipitant. SrFe 12O 19 nanoparticles were obtained by the molten salt method-assisted high-temperature calcinations. The results revealed that SrFe 12O 19nanoparticles with an average size of about 110 nm were obtained at 850 °C for 2 h and the product possessed regular hexangular morphology. The saturation ization of the product was approximately emu/g. (2) SrFe 12O 19nanoparticles were prepared using ethylene glycol (EG) assisted hydrothermal synthesis using Fe(NO 3) 3·9H 2O, Sr(NO 3) 2as the starting materials and NaOH as precipitant. Theeffect ofthe reaction temperature an