Study of Measurement Techniques for Strong Pulsed Magnetic Field

Author(s):  
Zhenhua Li ◽  
Qiuhui Li ◽  
Li Qiu ◽  
Qi Xiong ◽  
Changzheng Deng

Background: Currently, how to measure the magnetic field accurately is a difficulty in the study of strong magnetic field. Methods: This paper summarizes several methods of measurement techniques for strong pulsed magnetic field presently, the principles and characteristics of various measurement methods are compared and analyzed. The maximum measurement intensity of electromagnetic induction method can reach 103T. The magneto-optical effect method of Faraday can measure the magnetic field intensity of 0.1~10T, and the measurement error is within 10-2T. Results: The MOKE effect can measure a magnetic field intensity up to 100T, with an error 3×10-2T. The Zeeman effect can be measured in a magnetic field intensity of 1~20T. Conclusion: The existential problems of various methods are described. Lastly, some solutions are proposed according to the existential problems, and the development of measurement techniques for strong pulsed magnetic field in the future is prospected.

2018 ◽  
Vol 383 ◽  
pp. 185-189
Author(s):  
A.A. Fedotov ◽  
Alexander V. Pokoev ◽  
Sergiy V. Divinski

The impact of a pulsed magnetic field on Sn diffusion in α-Fe is investigated within the magnetic field intensity range of 79.6–398.0 kА/m and the frequency range of 1–21 Hz at 730, 740, and 750 °С. The solute diffusion coefficients were measured by X-ray diffraction analysis. The pulsed magnetic field was found to influence significantly the diffusion coefficients of Sn in α-Fe. A resonant maximum of the bulk diffusion coefficient is observed at the frequency of 13 Hz and the magnetic field intensity of 398.0 kА/m. Possible mechanisms of the established magneto-diffusion coupling are discussed.


2019 ◽  
Vol 7 (13) ◽  
pp. 3740-3743 ◽  
Author(s):  
Ying Li ◽  
Yue Long ◽  
Guoqiang Yang ◽  
Chen-Ho Tung ◽  
Kai Song

The wavelength of amplified spontaneous emission based on liquid magnetically responsive photonic crystals can be tuned by simply changing the magnetic field intensity.


Minerals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 609 ◽  
Author(s):  
Wan ◽  
Qu ◽  
Li ◽  
He ◽  
Bu ◽  
...  

Nonpolar hydrocarbon oil (NHO) is one of the most extensively used collectors in the flotation of molybdenite due to its excellent selectivity. However, NHO has low sensibility at pulp temperature. At low temperatures (<283 K), although more kerosene is used, the recovery of molybdenite flotation is still lower than at room temperature. In this study, magnetizing treatment, which is an efficient, low-cost, innovative, and environmentally friendly emulsification method, was used to improve the flotation performance of NHO in low-temperature molybdenite flotation. The test results showed that, compared with unmagnetized kerosene (UMK), the optimum dosage of magnetized kerosene (MK) could be reduced by 11% at 298 K. At the same dosage of kerosene, the flotation recovery of MK was 3% higher than UMK at 278 K. The surface tension measurement results showed that the surface tension of MK rose periodically as the magnetic field intensity increased, and there was a maximum surface tension within each period. Further, the magnetic field intensity had the maximum flotation recovery of molybdenite at the maximum surface tension of MK. Combined with the analysis based on the Girifalco–Good theory and the static drop volume method of interfacial tension, the interfacial tension of kerosene–water was shown to decrease with the increase of the surface tension of kerosene. This finding indicates that the dispersibility of kerosene in pulp could be improved by reducing the size of oil droplets, thereby improving the molybdenite flotation recovery of kerosene at low-temperature pulp. It is helpful to improve the flotation recovery of molybdenite using NHO as a collector for low-temperature pulp (<283 K).


2017 ◽  
Vol 898 ◽  
pp. 1783-1786
Author(s):  
Lei Zhang ◽  
Yi Su ◽  
Yu Lin Wu ◽  
Yao Liu ◽  
Yong Wang ◽  
...  

The viscosity of potassium dihydrogen phosphate, KH2PO4 (KDP), aqueous solution within magnetic field was studied. Experimental results showed that, the viscosity of saturated KDP solution exhibited multiple extreme values when the magnetic field intensity increased from 0 Gs to 2250 Gs. Influences of the magnetic field intensity on the viscosity of KDP solution were very complicated. It’s concerned with the temperature and the concentration of solution. As the KDP was produced from aqueous solution within magnetic field, the temperature and the concentration of solution also needed to be carefully controlled. Magnetic field with intensity values of 300 Gs, 600 Gs and 1800 Gs, all have the strong effects on the structures of KDP aqueous solution.


2020 ◽  
Author(s):  
Jeng-Hwa Yee ◽  
Jesper Gjerloev ◽  
Viacheslav Merkin ◽  
Karl Laundal

&lt;p&gt;The Zeeman effect of the O&lt;sub&gt;2&lt;/sub&gt; 118 GHz spectral radiance measurements can be utilized to remotely measure the magnetic field perturbations at altitudes close to the auroral electrojets. The technique has been demonstrated using the measurements provided by the Microwave Limb Souncer onboard the Aura spacecraft. &amp;#160;The derived current-induced magnetic field perturbations were found to be highly correlated with those coincidently obtained by ground magnetometers and to be consistent with the well-known auroral electrojet current distribution thereby providing a strong argument for the validity of the technique. With today's technology, a 118 GHz instrument, can be miniaturized allowing it to fly on small satellites such as CubeSats. &amp;#160;A constellation of small satellites with each one carrying a number of these identical mini-radiometers would have the ability to provide simultaneous multipoint measurement of the magnetic field perturbations at altitudes close to the electrojet, thereby greatly advancing our understanding of the ionospheric current system. &amp;#160;In this paper, we present the Zeeman magnetic field sensing technique, the requirements and specifications of the instrument, and an example of a cost effectively cubesat mission that provides unprecedented measurements of the evolution and structure of the auroral electrojet system.&lt;/p&gt;


Solar Physics ◽  
1990 ◽  
Vol 130 (1-2) ◽  
pp. 31-37 ◽  
Author(s):  
P. Zlobec ◽  
V. Ruždjak ◽  
B. Vršnak ◽  
M. Karlický ◽  
M. Messerotti

2013 ◽  
Vol 325-326 ◽  
pp. 353-358 ◽  
Author(s):  
Thosdeekoraphat Thanaset ◽  
Santalunai Samran ◽  
Thongsopa Chanchai

The performance improved of focusing deep hyperthermia inductive heating for breast cancer treatment using magnetic fluid nanoparticles with magnetic shielding system has been presented in the paper and the results are discussed. It is a technique challenge in hyperthermia therapy is to control locally heat the tumor region up to an appropriate temperature to destroy cancerous cells, without damaging the surrounding healthy tissue by using magnetic fluid nanoparticles and cylindrical metal shielding with aperture. We show that the magnetic field intensity can be controlled by changing the aperture size to suitable. In addition, the position of the heating can be controlled very well with the magnetic fluid together with shielding system. In the simulation, the inductive applicator is a ferrite core with diameter of 7 cm and excited by 4 MHz signal. Results have shown that the temperature increments depend on the magnetic fluid nanoparticles. In addition, the magnetic field intensity without damaging the surrounding healthy tissue when used magnetic shielded system. These results demonstrate that it is possible to achieve higher temperatures and to focus magnetic field intensity where the nanoparticles and magnetic shielding system are used.


1973 ◽  
Vol 51 (3) ◽  
pp. 266-276 ◽  
Author(s):  
R. L. Meyer ◽  
G. Leclert ◽  
M. Felden

We study the influence of the magnetic field intensity and direction with respect to the wave vector on the scattering cross-section resonances. We deduce the best experimental conditions for studying these resonances. It is shown that the spectrum modulation of the scattered wave can be used to measure, in some configurations, the confining magnetic field direction.


2012 ◽  
Vol 488-489 ◽  
pp. 1451-1456
Author(s):  
Rong Hua Ma ◽  
Jian Hao Zhong

The purpose of this study is to develop a micro electro-magnetic actuator manufactured by MEMS-based fabrication and electroplating techniques. This actuator presented a novel technique in the electromagnetic fabrication and smaller physical size than the traditional counterparts for micro actuators and provides a faster response time and lower cost. A micro coil structure is released from FeCl3 etchant and bonded on a thin film (Parafilm”M”, Pechiney Plastic Packaging Inc.) to achieve an actuator-membrane structure. When an external AC power is applied to a micro coil, a magnetic field is created to attract and repel through an NdFeB permanent magnet, and the displacement of the membrane is increased as a current of AC power. The results show the measured magnetic field intensity weakens as the distance between the coil and the Gauss meter probe increases. However, it is observed that the magnetic field intensity does not increase linearly with the number of series coils, which is due to the distance between series coils.


Sign in / Sign up

Export Citation Format

Share Document