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无惰性气体保护Fe3O4纳米球的超声法制备及表征 总被引:1,自引:0,他引:1
在无惰性气体保护、不添加表面活性剂、超声处理条件下加入亚硫酸钠,采用化学共沉淀结合超声辅助法制备纳米四氧化三铁,经X射线衍射、透射电子显微镜和材料综合性能测量系统等对产物进行了表征。结果表明,所制备的样品为反尖晶石结构的Fe3O4纳米球,平均粒径约为15 nm,饱和磁化强度最高达75.49 emu/g;n(Fe3+)/n(Fe2+)比率、沉淀剂和Na2SO3对磁性都具有明显的影响;该Fe3O4纳米球具有优良的水中Hg2+的吸附去除率,在吸附60 min后,最高可达99%,显示出很强的纳米效应,是一种具有较好应用前景的Hg2+吸附剂。 相似文献
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Fe3O4@m-SiO2磁性纳米颗粒的制备及其药物缓释行为 总被引:1,自引:0,他引:1
采用溶胶-凝胶法制备Fe3O4@m-SiO2磁性纳米颗粒,通过乙醇回流法或煅烧法去除模板剂分别获得了单介孔和双介孔磁性纳米颗粒。利用X射线衍射、Fourier变换红外光谱、Zeta电位仪、透射电子显微镜、低温氮吸附比表面测试仪和振动样品磁强计对其物相、结构和性能进行了表征。选用维生素B12为模型药物,研究了两种介孔材料的药物缓释行为。结果表明:Fe3O4@m-SiO2磁性纳米颗粒尺寸在60~80 nm之间;单介孔和双介孔磁性纳米颗粒的比饱和磁化强度和药物装载量分别达到51、55 A.m2/kg和104.5、110.3 mg/g;在药物缓释过程中,两种介孔材料的释药量均达到80%以上,其中,单介孔材料更有利于药物缓释。 相似文献
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选用无规则、正八面体和六方片状形貌的纳米Fe3O4磁性颗粒作为磁流体固相材料,通过设计组装基于L–C振荡电路的磁流体稳定性测试仪,确定制备稳定磁流体的较佳表面改性活性剂和辅助表面活性剂用量。同时,对含有不同形貌磁性颗粒的磁流体在水平方向磁场以及竖直方向磁场中的磁流变学性能进行了研究。结果表明:在外加水平方向180、350、500Gs磁感应强度,磁流体的黏度、剪切应力基本不变,磁流体表现出Newtonian流体的流变学特性;在外加竖直方向360、740、1130Gs磁感应强度,磁流体表现出Bingham流体的流变学特性;对于含有正八面体形貌纳米Fe3O4颗粒的磁流体,其黏度和剪切应力随外加磁场的变化较大。 相似文献
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Fe3O4/C复合材料是一类有潜力的锂离子电池负极材料,但是其较低的电导率和显著的体积效应导致循环稳定性不够理想。采用静电纺丝技术,以乙酰丙酮铁和聚丙烯腈(PAN)为前驱体制备Fe3O4/C复合纳米纤维自支撑电极,通过在纺丝液中添加聚甲基丙烯酸甲酯(PMMA)引入孔隙缓解体积效应,通过高速收丝技术形成取向纤维膜以提高自支撑电极导电性。采用扫描电子显微镜(SEM)、X射线衍射仪(XRD)、拉曼光谱仪、热重分析仪(TG)、X射线光电子能谱仪(XPS)、比表面积测试仪(BET)和电池测试系统,对所制备的电极材料的形貌结构和电化学性能进行表征。研究表明:PMMA的引入显著增加了中孔和大孔数量,高速收丝下纤维排列更加有序。孔隙的增加显著提高了Fe3O4/C复合纳米纤维膜的比容、倍率性能和循环稳定性。所得的取向多孔Fe3O4/C复合纳米纤维膜具有710 mAh/g的高可逆容量,在1.0 A/g电流密度下经过500次循环后依然... 相似文献
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纳米Fe3O4具有独特的性质,如超顺磁性、尺寸小和低毒性,且易在外磁场下分离,近几年来在石油开发领域受到广泛的关注。本文综述了磁性Fe3O4纳米颗粒(NPs)的生物合成及其在提高采收率(EOR)的应用,首先介绍了微生物、植物提取液和动物合成磁铁矿:微生物的合成主要包括两个过程,一是对金属离子的吸附,二是还原矿化作用;植物提取液的合成依赖水溶性的一些代谢物,如多酚、生物碱和柠檬酸等的作用;动物体中也发现了磁铁矿,可以感应地磁场从而判断方向。然后阐述了Fe3O4 NPs的EOR机理和应用:Fe3O4 NPs可以将油滴包裹形成稳定的乳液,降低界面张力,改变润湿性,通过增加驱替流体的黏度和降低重油的黏度来提高波及效率以及楔形结构产生分离压力。在此作用下,总结了磁性Fe3O4在EOR方面的应用。 相似文献
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采用Fe3O4分别与BaO、Ba(OH)2在不同质量配比物理混合后对六氯苯(HCB)在反应温度为300℃、时间为10 min的条件下进行了降解研究。结果发现BaO、Ba(OH)2分别与Fe3O4物理混合后对HCB的降解效率都高于各单一组分,表明不仅Fe3O4与BaO的混合物对HCB的降解存在协同降解效应,而且Fe3O4与Ba(OH)2的混合物对HCB的降解也存在协同降解效应,且这种协同效应能促进HCB的深度加氢脱氯。而不同质量配比的Fe3O4与Ba(OH)2、BaO混合物表现出不同的活性,当质量配比为40∶10时降解活性最高,分别为96.2%、91.5%。根据降解产物分析,推测了Fe3O4与Ba(OH)2混合物对HCB的协同加氢脱氯降解机制。 相似文献
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具有良好的化学稳定性、生物相容性、磁响应性的单分散磁性Fe3O4纳米粒子,在药学、催化化学、医学和光电磁记录材料等方面都有很大的使用前景;而具有自组装光子晶体现象的Fe3O4磁性纳米粒子在包装、印刷、防伪等领域的应用中更展现出巨大的潜力。本文在对单分散磁性Fe3O4纳米粒子的制备方法进行了总结回顾,并对单分散磁性Fe3O4纳米粒子的光学应用领域做了简略的介绍,并对单分散磁性Fe3O4纳米粒子的发展趋向进行了展望,并总结分析现阶段大多数Fe3O4纳米粒子的合成方法在非极性溶液中分散性差,使其在实际应用中受到很大的限制,未来Fe3O4纳米粒子表面进行修饰将成为该领域的研究热点之一。 相似文献
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Mehdi Amani 《Polymer-Plastics Technology and Engineering》2020,59(17):1910-1931
ABSTRACT In this article, water-based epoxy–acrylate (EP/AC) emulsion coatings and its nanocomposites with Fe3O4 nanoparticles, graphene oxide nanosheets and graphene oxide which was decorated with Fe3O4 nanoparticles were synthesized. This was executed by means of a pre-emulsion seeded semi-batch emulsion polymerization handle with a blend of conventional anionic surfactant (Polyalkylene glycol ether sulfate, ammonium salt-EXOSEL 20 S) and typical nonionic type emulsifier (Octylphenol polyoxyethylene ether OP-10) for emulsion polymerization (schematic 1). Prepared nanoparticles were investigated with different analyzing methods like FT-IR, XRD, SEM-EDAX and TGA. The impact of the distinctive nanostructures in an (EP/AC) resin, on coated steel panels with the features of corrosion conservation, was investigated by the test of electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. Morphology of surface and thermal behavior of nanocomposite tests were executed using surface filtering electron microscopy (FE-SEM) and thermal gravimetric analysis (TGA). Different analyses resulted from nanostructures and nanocomposites approved very good dispersion of fillers in nanocomposite beads. Besides, they indicate the effective role of nanoparticles especially graphene oxide which was decorated with Fe3O4 nanoparticles in corrosion resistance of water-based EP/AC coatings and other properties of coated instances. 相似文献
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以硬脂酸铅为单源前驱体,成功制备出硬脂酸修饰的氧化亚铅纳米颗粒,用透射电子显微镜、X-射线粉末衍射仪、红外光谱仪等仪器对其进行了结构表征,并在四球摩擦试验机上测试了其抗磨性能。结果表明:所制备的Pb2O纳米颗粒大小均匀,表面修饰层与纳米颗粒表面之间发生化学键合作用,其作为润滑油添加剂具有良好的抗磨能力。 相似文献
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Masatoshi Watanabe Misao Yoneda Ayaka Morohashi Yasuki Hori Daiki Okamoto Akiko Sato Daisuke Kurioka Tadashi Nittami Yoshifumi Hirokawa Taizo Shiraishi Kazuaki Kawai Hiroshi Kasai Yukari Totsuka 《International journal of molecular sciences》2013,14(8):15546-15560
Fe3O4 magnetic nanoparticles (MgNPs-Fe3O4) are widely used in medical applications, including magnetic resonance imaging, drug delivery, and in hyperthermia. However, the same properties that aid their utility in the clinic may potentially induce toxicity. Therefore, the purpose of this study was to investigate the cytotoxicity and genotoxicity of MgNPs-Fe3O4 in A549 human lung epithelial cells. MgNPs-Fe3O4 caused cell membrane damage, as assessed by the release of lactate dehydrogenase (LDH), only at a high concentration (100 μg/mL); a lower concentration (10 μg/mL) increased the production of reactive oxygen species, increased oxidative damage to DNA, and decreased the level of reduced glutathione. MgNPs-Fe3O4 caused a dose-dependent increase in the CD44+ fraction of A549 cells. MgNPs-Fe3O4 induced the expression of heme oxygenase-1 at a concentration of 1 μg/mL, and in a dose-dependent manner. Despite these effects, MgNPs-Fe3O4 had minimal effect on cell viability and elicited only a small increase in the number of cells undergoing apoptosis. Together, these data suggest that MgNPs-Fe3O4 exert little or no cytotoxicity until a high exposure level (100 μg/mL) is reached. This dissociation between elevated indices of cell damage and a small effect on cell viability warrants further study. 相似文献
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In this work, we designed a magnetically-separable Fe3O4-rGO-ZnO ternary catalyst, ZnO anchored on the surface of reduced graphene oxide (rGO)-wrapped Fe3O4 magnetic nanoparticles, where rGO, as an effective interlayer, can enhance the synergistic effect between ZnO and Fe3O4. The effects of three operational parameters, namely irradiation time, hydrogen peroxide dosage, and the catalyst dosage, on the photo-Fenton degradation of methylene blue and methyl orange were investigated. The results showed that the Fe3O4-rGO-ZnO had great potential for the destruction of organic compounds from wastewater using the Fenton chemical oxidation method at neutral pH. Repeatability of the photocatalytic activity after 5 cycles showed only a tiny drop in the catalytic efficiency. 相似文献