Dissertation > Excellent graduate degree dissertation topics show

Preparation of Nano-fe 3 O 4 Particles Induced by Weak Exterior Magnetic Fieldand Magnetic Fluid Stability Study

Author: GuoLei
Tutor: HuXiaoFang
School: South China University of Technology
Course: Chemical Process Equipment
Keywords: Fe3O4 nano-particles weak magnetic field induction oxidation precipitation method stability silane coupling agent
CLC: TB383.1
Type: Master's thesis
Year: 2010
Downloads: 170
Quote: 0
Read: Download Dissertation

Abstract


Magnetic fluid was a colloidal system with magnetic nano-particles dispersed in the stable liquid phase. It combined the magnetism of the solid with the fluidity of the liquid, showing a magnetic, optical and other special phenomenon. Magnetic fluid was widely used in the aerospace, electronics, chemicals, machinery, energy, metallurgy, environmental protection, bio-medical and other fields. The preparation of magnetic fluid was a complex technological process, requiring the magnetic fluid in the rheological property to be controlled, stable and reliable. Therefore, the process involved to the magnetic particle gain, the surface active agent and the determination of the base fluid, the method and so on. This paper focused on the appropriate method of magnetic nano-particles preparation, maintaining the dispersion of magnetic particles and magnetic fluid stability.In this paper, a specific morphology of Fe3O4 nano-particles was firstly prepared by oxidation of the co-precipitation method under the weak magnetic field. The results showed that the size distribution of Fe3O4 magnetic particles became narrow, the average particle size and crystal size became larger. And the weak magnetic field could induceα-FeOOH to transform to be Fe3O4 accelerately. There was also a secondary nucleation and the morphology of secondary growth synthesis in the production of Fe3O4 nano-particles.Secondly, silane coupling agent KH560 was used as a surfactant of Fe3O4 magnetic fluid; in order to obtain better stability of magnetic fluid, this paper added a secondary dispersant Span80 to enhance stability. Through comparative experiments, the optimal amount of KH560 and Span80 were determined. Experimental results showed that the magnetic fluid in the 20# engine oil has a better dispersion, when the KH560 concentration was 1.5% and secondary dispersant Span80 was 3% by the reaction of initial surface modification.Finally, this paper provided a method of the magnetic fluid preparation when nano-Fe3O4 magnetic particles as a carrier, silane coupling agent KH560 as surfactant and Span80 as Secondary dispersing agent in the 20# oil-based fluid. The method of preparation improved the effect of stability; and the way is simple, operable, low cost and high efficiency.

Related Dissertations

  1. Analysis and Study of Abutment Stability in Concrete High Arch Dam by Three-Dimensional Nonlinear Finite Element Method,TV642.4
  2. The Study on Structural Calculation and Analysis Method of Lattice-type Crane with Variable Cross-section Boom,TH21
  3. Power System Dynamic Voltage Stability Simulation Study Based on Precise Integration Method,TM712
  4. Simulation and Analysis about Switched Reluctance Generator Power Supply System,TM31
  5. Research and Design for the Laser’s Power Control System of Laser Direct Writing,TN249
  6. Stability Analysis of Systems with Time Delays,TP13
  7. Research on Input-To-State Stability of Discrete-Time Nonlinear Systems,TP13
  8. Stability Analysis of Roller Compacted Concrete Gravity Dam Based on Time-history Method,TV642.2
  9. Thermal Stability of Complexes of Chitosan Quaternary Ammonium Salt and Metal Ion,O634
  10. Synthesis and Application of the chloro- methoxy fatty acid methyl esters,TQ414.8
  11. Breeding of High-Yield Pigment Production Monascus and Studies on Pigments’ Qualities,TS202.3
  12. On Ohba’s Conjecture of One Class of Complete Multipartite Graphs,O157.5
  13. Analysis of the Impact of Tailings Dam Stability under Seepage Role,TV649
  14. Research on Anti-periodic Solutions of Delayed Cellular Neural Networks without Assuming Global Lipschitz Conditions,TP183
  15. Characterization and Properties of capsaicin / CD system,TQ450.1
  16. Preparation and Properties of lead-free glass powder,TQ171.6
  17. Preparation and Evaluation on the Toxicological Safety and Stability of Deer Blood Wine,TS262.91
  18. Evaluation on Stability of Threshing and Redrying Lamina Structure of Tobacco,TS443
  19. Effects of Continous Super Rice Planting on Contrnt of Organic Carbon and Aggregates Stability in Paddr Soils,S511
  20. Study on Attention Characteristcs of Chinese Paralympic Table Tennis Players,G846
  21. Syntheses, Structures and Properties of Metal-organic Frameworks Based on Dicarboxylate Ligands,O621.13

CLC: > Industrial Technology > General industrial technology > Materials science and engineering > Special structural materials
© 2012 www.DissertationTopic.Net  Mobile