scholarly journals A simulation study of excitation coil design in single-sided mpi scanner for human body application

2019 ◽  
Vol 8 (4) ◽  
Author(s):  
Nurmiza Othman ◽  
Muhamad Fikri Shahkhirin Birahim ◽  
Wan Nurshazwani Wan Zakaria ◽  
Mohd Razali Md Tomari ◽  
Md Nor Ramdon Baharom ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Physical Properties ◽  
Human Body ◽  
Simulation Study ◽  
Complex Surface ◽  
Imaging Method ◽  
Magnetic Field Generation ◽  
Excitation Coil ◽  
Particle Imaging

Magnetic particle imaging (MPI), a tomographic imaging method has been introduced for 3D imaging of human body with some potential applications such as magnetic hyperthermia and cancer imaging. It involves three important elements: tracer development using magnetic nanoparticles (MNPs), hardware realization (scanner using excitation and pickup coils), and image reconstruction optimization. Their combination will produce a high quality of image taken from any biological tissue in the human body based on the secondary magnetic field signal from the magnetized MNPs that are injected into human body. A homogeneous and adequate magnetic field strength from an excitation coil is needed to enhance the quality of the secondary signal. However, the complex surface topography of human body and physical properties of an excitation coil influence the strength and the homogeneity of the magnetic field generation at the MNPs. Therefore, this work focused on finding alternative design of excitation coil used in single sided MPI to produce up to 2 mT with high homogeneity of field distribution in the MNPs at the varied depth of 10 to 30 mm under the excitation coil. We proposed several designs with variation in physical properties and coil arrangement based on simulation study carried out by using Ansys Maxwell.

The Electro-Hydraulic Control Directional Valve Based on Magneto-Rheological Fluid

2013 ◽  
Vol 567 ◽  
pp. 139-142
Author(s):  
D.D. Liu ◽  
C.R. Tang ◽  
C. Zhao
Keyword(s):  
Magnetic Field ◽  
External Magnetic Field ◽  
Control Valve ◽  
Piping System ◽  
Manufacturing Cost ◽  
Hydraulic Control ◽  
Hydraulic Support ◽  
Excitation Coil ◽  
Magneto Rheological

The electro-hydraulic control directional valve based on magneto-rheological fluid using in hydraulic support is proposed. The magneto-rheological fluid represents favorable flow liquid state without external magnetic field, but it can represent mechanics quality of similarity solid in strong magnetic field. The magneto-rheological fluid may become solid within milliseconds under the action of an external magnetic field, which can realize intelligent control of hydraulic system and overcome shortcoming of traditional hydraulic valve. The electro-hydraulic control directional valve uses magneto-rheological fluid as controlling fluid, and adjusts pressure difference of action main control valve between left end and right end though changing excitation coil current of magneto-rheological valve. The electro-hydraulic control directional valve based on magneto-rheological fluid can satisfy the self-feeding hydraulic support using requirements and has low manufacturing cost. The installation and using of the electro-hydraulic control valve is more convenient and fast. It reduces the point of failure of the hydraulic supports piping system and makes hydraulic support more secure and reliable.

Pengaruh Penambahan Air pada Pengolahan Susu Kedelai

2015 ◽  
Vol 4 (1) ◽  
pp. 8-13
Author(s):  
Priscillia Picauly ◽  
Josefina Talahatu ◽  
Meitycorfrida Mailoa
Keyword(s):  
Glycine Max ◽  
Physical Properties ◽  
Sweet Taste ◽  
Soya Milk ◽  
Randomized Design ◽  
Soybean Extract ◽  
Glycine Max L ◽  
Completely Randomized Design ◽  
Water Ratio

Soybean (Glycine max (L) Merr) is needed as an alternative diversification in order to increase protein consumption. Soybean can be processed into variety of foods and drinks. The most popular drink from soybean is soya milk which is made from soybean extract yielded from the addition of water. The amount of water added determine the quality of soya milk due to its effect on the chemical and physical properties of soya milk. This research was intended to find out the proper ratio of soybean and water in the processing of soya milk to yield the best quality. A completely randomized design was used with eight treatments of soybean and water ratio as follows, ratio of 1 : 6, ratio of 1 : 8, ratio of 1 : 10, ratio of 1 : 12, ratio of 1 : 14, ratio of 1 : 16, ratio of 1 : 18 and ratio of 1 : 20. Result showed the soybean and water ratio 1 : 10 in the processing of soya milk yielded milk having good quality according to its chemical with protein content of 2.53%, fat of 1.20%, sugar total of 1.60%, pH of 7.1, and organoleptic characteristies of both somewhat sweet taste and viscous texture.

scholarly journals An 84-μG Magnetic Field in a Galaxy at Z=0.692?

2008 ◽  
Vol 4 (S254) ◽  
pp. 95-96
Author(s):  
Arthur M. Wolfe ◽  
Regina A. Jorgenson ◽  
Timothy Robishaw ◽  
Carl Heiles ◽  
Jason X. Prochaska
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Faraday Rotation ◽  
Large Scale ◽  
Dynamo Model ◽  
Magnetic Field Generation ◽  
Interstellar Gas ◽  
Splitting Technique ◽  
Average Value ◽  
The Magnetic Field

AbstractThe magnetic field pervading our Galaxy is a crucial constituent of the interstellar medium: it mediates the dynamics of interstellar clouds, the energy density of cosmic rays, and the formation of stars (Beck 2005). The field associated with ionized interstellar gas has been determined through observations of pulsars in our Galaxy. Radio-frequency measurements of pulse dispersion and the rotation of the plane of linear polarization, i.e., Faraday rotation, yield an average value B ≈ 3 μG (Han et al. 2006). The possible detection of Faraday rotation of linearly polarized photons emitted by high-redshift quasars (Kronberg et al. 2008) suggests similar magnetic fields are present in foreground galaxies with redshifts z > 1. As Faraday rotation alone, however, determines neither the magnitude nor the redshift of the magnetic field, the strength of galactic magnetic fields at redshifts z > 0 remains uncertain.Here we report a measurement of a magnetic field of B ≈ 84 μG in a galaxy at z =0.692, using the same Zeeman-splitting technique that revealed an average value of B = 6 μG in the neutral interstellar gas of our Galaxy (Heiles et al. 2004). This is unexpected, as the leading theory of magnetic field generation, the mean-field dynamo model, predicts large-scale magnetic fields to be weaker in the past, rather than stronger (Parker 1970).The full text of this paper was published in Nature (Wolfe et al. 2008).

scholarly journals Predictions of the geomagnetic secular variation based on the ensemble sequential assimilation of geomagnetic field models by dynamo simulations

2020 ◽  
Vol 72 (1) ◽  
Author(s):  
Sabrina Sanchez ◽  
Johannes Wicht ◽  
Julien Bärenzung
Keyword(s):  
Magnetic Field ◽  
Secular Variation ◽  
Geomagnetic Field ◽  
Wave Number ◽  
Main Magnetic Field ◽  
Candidate Model ◽  
Uncertainty Estimates ◽  
Geomagnetic Field Models ◽  
Dipole Configuration

Abstract The IGRF offers an important incentive for testing algorithms predicting the Earth’s magnetic field changes, known as secular variation (SV), in a 5-year range. Here, we present a SV candidate model for the 13th IGRF that stems from a sequential ensemble data assimilation approach (EnKF). The ensemble consists of a number of parallel-running 3D-dynamo simulations. The assimilated data are geomagnetic field snapshots covering the years 1840 to 2000 from the COV-OBS.x1 model and for 2001 to 2020 from the Kalmag model. A spectral covariance localization method, considering the couplings between spherical harmonics of the same equatorial symmetry and same azimuthal wave number, allows decreasing the ensemble size to about a 100 while maintaining the stability of the assimilation. The quality of 5-year predictions is tested for the past two decades. These tests show that the assimilation scheme is able to reconstruct the overall SV evolution. They also suggest that a better 5-year forecast is obtained keeping the SV constant compared to the dynamically evolving SV. However, the quality of the dynamical forecast steadily improves over the full assimilation window (180 years). We therefore propose the instantaneous SV estimate for 2020 from our assimilation as a candidate model for the IGRF-13. The ensemble approach provides uncertainty estimates, which closely match the residual differences with respect to the IGRF-13. Longer term predictions for the evolution of the main magnetic field features over a 50-year range are also presented. We observe the further decrease of the axial dipole at a mean rate of 8 nT/year as well as a deepening and broadening of the South Atlantic Anomaly. The magnetic dip poles are seen to approach an eccentric dipole configuration.

Magnetic-field-induced self-assembly of FeCo/CoFe2O4 core/shell nanoparticles with tunable collective magnetic properties

Nanoscale ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 4519-4529
Author(s):  
J. Mohapatra ◽  
J. Elkins ◽  
M. Xing ◽  
D. Guragain ◽  
Sanjay R. Mishra ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Magnetic Properties ◽  
Physical Properties ◽  
Self Assembly ◽  
Core Shell ◽  
Shell Nanoparticles ◽  
Novel Approach ◽  
Core Shell Nanoparticles

Self-assembly of nanoparticles into ordered patterns is a novel approach to build up new consolidated materials with desired collective physical properties.

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