Silicon with Magnetic Nanoclusters of Manganese Atoms as a New Ferromagnetic Material

Abstract The University of Malaya Medical Centre, Kuala Lumpur had acquired a intraoperative MRI (iMRI) brain suite via a public private initiative in September 2015. The MRI brain suite has a SIEMENS 1.5T system with NORAS coil system and NORAS head clamps in a two room solution. We would like to retrospectively review the cranial paediatric neuro-oncology cases that had surgery in this facility from September 2015 till December 2019. We would like to discuss our experience with regard to the clear benefits and the challenges in using such technology to aid in the surgery. The challenges include the physical setting up the paediatric case preoperatively, the preparation and performing the intraoperative scan, the interpretation of intraoperative images and making a decision and the utilisation of the new MRI data set to assist in the navigation to locate the residue safely. Also discuss the utility of the intraoperative images in the decision of subsequent adjuvant management. The use of iMRI also has other technical challenges such as ensuring the perimeter around the patient is free of ferromagnetic material, the process of transfer of the patient to the scanner and as a consequence increased duration of the surgery. CONCLUSION: Many elements in the use of iMRI has a learning curve and it improves with exposure and experience. In some areas only a high level of vigilance and SOP (Standard operating procedure) is required to minimize mishaps. Currently, the iMRI gives the best means of determining extent of resection before concluding the surgery.

Download Full-text

Magneto-optical design of anomalous Nernst thermopile

Scientific Reports ◽

10.1038/s41598-021-90865-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jian Wang ◽

Asuka Miura ◽

Rajkumar Modak ◽

Yukiko K. Takahashi ◽

Ken-ichi Uchida

Keyword(s):

Optical Design ◽

Polarized Light ◽

Ferromagnetic Material ◽

Light Polarization ◽

Optical Recording ◽

Induced Voltage ◽

Large Area ◽

Circularly Polarized Light ◽

Out Of Plane ◽

Order Of Magnitude

AbstractThe introduction of spin caloritronics into thermoelectric conversion has paved a new path for versatile energy harvesting and heat sensing technologies. In particular, thermoelectric generation based on the anomalous Nernst effect (ANE) is an appealing approach as it shows considerable potential to realize efficient, large-area, and flexible use of heat energy. To make ANE applications viable, not only the improvement of thermoelectric performance but also the simplification of device structures is essential. Here, we demonstrate the construction of an anomalous Nernst thermopile with a substantially enhanced thermoelectric output and simple structure comprising a single ferromagnetic material. These improvements are achieved by combining the ANE with the magneto-optical recording technique called all-optical helicity-dependent switching of magnetization. Our thermopile consists only of Co/Pt multilayer wires arranged in a zigzag configuration, which simplifies microfabrication processes. When the out-of-plane magnetization of the neighboring wires is reversed alternately by local illumination with circularly polarized light, the ANE-induced voltage in the thermopile shows an order of magnitude enhancement, confirming the concept of a magneto-optically designed anomalous Nernst thermopile. The sign of the enhanced ANE-induced voltage can be controlled reversibly by changing the light polarization. The engineering concept demonstrated here promotes effective utilization of the characteristics of the ANE and will contribute to realizing its thermoelectric applications.

Download Full-text

Time-Response-Histogram-Based Feature of Magnetic Barkhausen Noise for Material Characterization Considering Influences of Grain and Grain Boundary under In Situ Tensile Test

Sensors ◽

10.3390/s21072350 ◽

2021 ◽

Vol 21 (7) ◽

pp. 2350

Author(s):

Jia Liu ◽

Guiyun Tian ◽

Bin Gao ◽

Kun Zeng ◽

Yongbing Xu ◽

...

Keyword(s):

Grain Boundary ◽

Tensile Stress ◽

Material Properties ◽

Ferromagnetic Material ◽

Silicon Steel ◽

Time Response ◽

Barkhausen Noise ◽

Time Interval ◽

Magnetic Barkhausen Noise

Stress is the crucial factor of ferromagnetic material failure origin. However, the nondestructive test methods to analyze the ferromagnetic material properties’ inhomogeneity on the microscopic scale with stress have not been obtained so far. In this study, magnetic Barkhausen noise (MBN) signals on different silicon steel sheet locations under in situ tensile tests were detected by a high-spatial-resolution magnetic probe. The domain-wall (DW) motion, grain, and grain boundary were detected using a magneto-optical Kerr (MOKE) image. The time characteristic of DW motion and MBN signals on different locations was varied during elastic deformation. Therefore, a time-response histogram is proposed in this work to show different DW motions inside the grain and around the grain boundary under low tensile stress. In order to separate the variation of magnetic properties affected by the grain and grain boundary under low tensile stress corresponding to MBN excitation, time-division was carried out to extract the root-mean-square (RMS), mean, and peak in the optimized time interval. The time-response histogram of MBN evaluated the silicon steel sheet’s inhomogeneous material properties, and provided a theoretical and experimental reference for ferromagnetic material properties under stress.

Download Full-text

Temperature and thickness dependent magnetization reversal in 2D layered ferromagnetic material Fe3GeTe2

Journal of Magnetism and Magnetic Materials ◽

10.1016/j.jmmm.2020.167719 ◽

2021 ◽

Vol 527 ◽

pp. 167719

Author(s):

Jun-jie Guo ◽

Qing-lin Xia ◽

Xi-guang Wang ◽

Yao-zhuang Nie ◽

Rui Xiong ◽

...

Keyword(s):

Magnetization Reversal ◽

Ferromagnetic Material

Download Full-text

FEM‐PEEC coupled method for modeling solid conductors in the presence of ferromagnetic material

COMPEL The International Journal for Computation and Mathematics in Electrical and Electronic Engineering ◽

10.1108/03321640810878324 ◽

2008 ◽

Vol 27 (4) ◽

pp. 904-910 ◽

Cited By ~ 2

Author(s):

T‐S. Tran ◽

G. Meunier ◽

P. Labie ◽

Y. Le Floch ◽

J‐M. Guichon ◽

...

Keyword(s):

Ferromagnetic Material ◽

Coupled Method ◽

Solid Conductors

Download Full-text

Magnetic shielding of an accelerator beam using passive ferromagnetic material

IEEE Transactions on Magnetics ◽

10.1109/20.511422 ◽

1996 ◽

Vol 32 (4) ◽

pp. 2663-2666 ◽

Cited By ~ 3

Author(s):

A. Koski ◽

S.L. Wipf

Keyword(s):

Ferromagnetic Material ◽

Magnetic Shielding

Download Full-text

Homogenization of composite ferromagnetic materials

Proceedings of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rspa.2015.0365 ◽

2015 ◽

Vol 471 (2182) ◽

pp. 20150365 ◽

Cited By ~ 5

Author(s):

François Alouges ◽

Giovanni Di Fratta

Keyword(s):

Free Energy ◽

Ferromagnetic Material ◽

Energy Functional ◽

Ferromagnetic Materials ◽

Rigorous Derivation ◽

Free Energy Functional ◽

Landau Free Energy ◽

Ferromagnetic Body ◽

The Media

The objective of this paper is to perform, by means of Γ - convergence and two-scale convergence , a rigorous derivation of the homogenized Gibbs–Landau free energy functional associated with a composite periodic ferromagnetic material, i.e. a ferromagnetic material in which the heterogeneities are periodically distributed inside the media. We thus describe the Γ -limit of the Gibbs–Landau free energy functional, as the period over which the heterogeneities are distributed inside the ferromagnetic body shrinks to zero.

Download Full-text

Application of Magnetoelastic Effect of Ferromagnetic Material in Stress Measurement

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.496.306 ◽

2012 ◽

Vol 496 ◽

pp. 306-309 ◽

Cited By ~ 2

Author(s):

Yan Ping Shi ◽

Shu Hua Fan

Keyword(s):

Mathematical Model ◽

Stress Measurement ◽

Ferromagnetic Material ◽

Induced Voltage ◽

Practical Application ◽

Magnetic Pole ◽

Magnetoelastic Effect ◽

Voltage Output ◽

Contact Sensor ◽

Test Result

A new non-contact sensor with three magnetic pole based on magnetoelastic effect was designed, and its operation principle and mathematical model of induced voltage output were given. The output characteristic of the sensor affected by field current intensity, frequency, and the gap between the probe of the sensor and the surface of the material tested was analyzed by testing. The calculation result based on the output model found by the paper accord basically with the test result. The results of the test have showed that the measuring precision and sensitivity of the sensor can meet the demands of the general practical application.

Download Full-text