Reconfiguring nanostructures in magnetic fluids using pH and magnetic stimulus for tuning optical properties

Both pure Fe 3 O 4 magnetic fluids and containing polystyrene sphere composite magnetic fluids have been prepared. The magneto-optical characteristics such as magnetic birefringence and linear dichroism of both magnetic fluids and composite magnetic fluids have been investigated by the magneto-optically modulated double-frequency method. The results reveal that the order structure of nonmagnetic spheres and the interactions between the spheres and the neighbor magnetic chains of Fe 3 O 4 particles in the composite magnetic fluids strongly affect the magneto-optical properties. The magneto-optical properties from the study can be used for further development of related new optical devices.

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The Presented Study of Zn-Cu Ferrites for Their Application in “Photocatalytic Activities”

10.5772/intechopen.99535 ◽

2021 ◽

Author(s):

Sathyaseelan Balaraman ◽

Baskaran Iruson ◽

Senthilnathan Krishnmoorthy ◽

Manikandan Elayaperumal

Keyword(s):

Optical Properties ◽

Magnetic Fluids ◽

Vital Role ◽

Soft Magnetic Materials ◽

High Resistivity ◽

Synthesis And Characterization ◽

Soft Magnetic ◽

Wide Range ◽

Photocatalytic Activities

The present chapter summarizes the synthesis and characterization of Zinc Copper (ZnCu) ferrites due to their wide range of applications in many areas. ZnCu ferrites are soft magnetic materials that have exceptional electrical, magnetic, and optical properties. ZnCu ferrites possess high resistivity, permeability, permittivity, saturation magnetization and low power losses, and coercivity. The above features of ZnCu ferrites find application in designing transformers, transducers, and inductors. Ferrites are also used in magnetic fluids, sensors, and biosensors. Apart from these advantages, they play a vital role in practical appliances like mobile, laptops, mobile chargers, refrigerators, washing machines, microwave ovens, printers, and so on. Therefore, the present focus is on the literature of techniques of the synthesis, their characterization, the effect of doping on the behavior of ZnCu ferrite, and, finally, their potential application in technology.

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Design of objective lens for 200-kV high-resolution electron microscopes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075361 ◽

1983 ◽

Vol 41 ◽

pp. 314-315

Author(s):

K. Tsuno ◽

T. Honda ◽

Y. Harada ◽

M. Naruse

Keyword(s):

Optical Properties ◽

Computer Technology ◽

Axial Magnetic Field ◽

Chromatic Aberration ◽

Objective Lens ◽

Resolution Electron ◽

Correction Of Astigmatism ◽

Three Stages ◽

Electron Microscopes ◽

Stage 1

Developement of computer technology provides much improvements on electron microscopy, such as simulation of images, reconstruction of images and automatic controll of microscopes (auto-focussing and auto-correction of astigmatism) and design of electron microscope lenses by using a finite element method (FEM). In this investigation, procedures for simulating the optical properties of objective lenses of HREM and the characteristics of the new lens for HREM at 200 kV are described.The process for designing the objective lens is divided into three stages. Stage 1 is the process for estimating the optical properties of the lens. Firstly, calculation by FEM is made for simulating the axial magnetic field distributions Bzc of the lens. Secondly, electron ray trajectory is numerically calculated by using Bzc. And lastly, using Bzc and ray trajectory, spherical and chromatic aberration coefficients Cs and Cc are numerically calculated. Above calculations are repeated by changing the shape of lens until! to find an optimum aberration coefficients.

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Optical Properties of HVEM Accelerators

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100114529 ◽

1975 ◽

Vol 33 ◽

pp. 180-181

Author(s):

A. Strojnik ◽

J.W. Scholl ◽

V. Bevc

Keyword(s):

Optical Properties ◽

Electron Accelerator ◽

Systematic Investigation ◽

Electron Source ◽

High Brightness ◽

The Past ◽

Wide Range ◽

Optical Behavior

The electron accelerator, as inserted between the electron source (injector) and the imaging column of the HVEM, is usually a strong lens and should be optimized in order to ensure high brightness over a wide range of accelerating voltages and illuminating conditions. This is especially true in the case of the STEM where the brightness directly determines the highest resolution attainable. In the past, the optical behavior of accelerators was usually determined for a particular configuration. During the development of the accelerator for the Arizona 1 MEV STEM, systematic investigation was made of the major optical properties for a variety of electrode configurations, number of stages N, accelerating voltages, 1 and 10 MEV, and a range of injection voltages ϕ0 = 1, 3, 10, 30, 100, 300 kV).

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