نتایج جستجو برای: fe3o4 magnetic nanoparticles

تعداد نتایج: 436976  

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه رازی - دانشکده علوم 1392

a novel acrylic acid-functionalized fe3o4 magnetic nanoparticle with a core-shell structure was developed for utilization as a heterogeneous organosuperacid in chemical transformations. the structural, surface, and magnetic characteristics of the nanosized catalyst were investigated by various techniques such as transmission electron microscopy (tem), thermogravimetric analysis (tga), and ft-ir...

Journal: :Journal of nanoscience and nanotechnology 2012
Huanxiang Sun Xin Zeng Ming Liu Sauli Elingarami Guopeng Li Bin Shen Nongyue He

We present a systematic study on the preparation, characteration and potential application of Fe3O4 and Fe3O4@SiO2 nanoparticles. Fe3O4 nanoparticles of controllable diameters were successfully synthesized by solvothermal system with tuning pH. The magnetic properties of nanoparticles were measured by vibration sample magnetometer. Fe3O4@ SiO2 nanoparticles were obtained via classic Stöber proc...

Journal: :international journal of nanoscience and nanotechnology 2011
z. khayat sarkar f. khayat sarkar

in this study, magnetic iron oxide nanoparticles (fe3o4) with the size range of 20-30 nm were prepared by the modified controlled chemical co-precipitation method from the solution of ferrous/ferric mixed salt-solution in alkaline medium. in this process polyethylene glycol was used as a surfactant to prevent the solution from agglomeration. the prepared magnetic nanoparticles were characterize...

2016
Junran Zhang Zhenyao Wu Minhao Zhang Wei Niu Ming Gao Ying Zhou Wenqing Liu Xuefeng Wang Rong Zhang Yongbing Xu

We demonstrated the effect of superparamagnetic Fe3O4 nanoparticles on Schottky barriers of graphene, in which the Fe3O4 nanoparticles were fabricated by a hydrothermal method and the single-layer graphene sheets were mechanically exfoliated from Kish graphite. The Fe3O4 nanoparticles were superparamagnetic with the saturation magnetic moment of about 32 emu/g at room temperature. We have found...

2014
Duangdao Channei Sukon Phanichphant

The Fe3O4/CeO2 magnetic photocatalyst was prepared by coating directly onto the surface of magnetic Fe3O4 particles. However a direct contact of CeO2 onto the surface of magnetic Fe3O4 particles presented unfavorable heterojunction, thus the SiO2 barrier layer between magnetic Fe3O4 and CeO2 was prepared as a core-shell stucture to reduce the negative effect by combining three steps of the hydr...

Journal: :Journal of the American Chemical Society 2008
Jinhao Gao Wei Zhang Pingbo Huang Bei Zhang Xixiang Zhang Bing Xu

We report a facile intracellular manipulation of fluorescent magnetic Fe3O4-CdSe nanoparticles using magnetic force. The growth of CdSe quantum dots on Fe3O4 nanoparticles produces Fe3O4-CdSe nanoparticles with two distinct properties, fluorescence and superparamagnetism. After nonspecific surface modification using glutathione (GSH), the hydrophilic Fe3O4-CdSe@GSH nanoparticles can be easily u...

2011
Meizhen Gao Wen Li Jingwei Dong Zhirong Zhang Bingjun Yang

The Fe3O4@SiO2 composite nanoparticles were obtained from as-synthesized magnetite (Fe3O4) nanoparticles through the modified Stöber method. Then, the Fe3O4 nanoparticles and Fe3O4@SiO2 composite nanoparticles were characterized by means of X-ray diffraction (XRD), Raman spectra, scanning electron microscope (SEM) and vibrating sample magnetometer (VSM). Recently, the studies focus on how to im...

2017
Ashwani Kumar Singh O. N. Srivastava Kedar Singh

In this article, we proposed a facile one-step synthesis of Fe3O4 nanoparticles of different shapes and sizes by co-precipitation of FeCl2 with piperidine. A careful investigation of TEM micrographs shows that the shape and size of nanoparticles can be tuned by varying the molarity of piperidine. XRD patterns match the standard phase of the spinal structure of Fe3O4 which confirms the formation...

Journal: :iranian journal of catalysis 2016
javad safari leila javadian

in this paper, fe3o4-chitosan nanoparticles were prepared by the immobilization of chitosan on the surface of fe3o4 nanoparticles. then, the 5-substituted hydantoins were synthesized from the condensation of aldehyde derivatives, ammonium carbonate and zinc cyanide as a well-known cyanating agent by the magnetic fe3o4-chitosan nanoparticles under neat conditions. fe3o4-chitosan nanocatalyst as ...

Journal: :international journal of nanoscience and nanotechnology 2015
e. ghasemi m. ghahari

in this research controlled coating of magnetite (fe3o4) nanoparticles with sio2 was investigated. the fe3o4 nanoparticles were synthesized via chemical co-precipitation and then coated by silica according to stober method. effects of tetra ethyl ortho silicate (teos) concentration and ethanol to teos on the coating thickness were investigated. x-ray powder diffraction, fourier transform infrar...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید