scholarly journals MNP-Enhanced Microwave Medical Imaging by Means of Pseudo-Noise Sensing

Sensors ◽  
2021 ◽  
Vol 21 (19) ◽  
pp. 6613
Author(s):  
Sebastian Ley ◽  
Jürgen Sachs ◽  
Bernd Faenger ◽  
Ingrid Hilger ◽  
Marko Helbig
Keyword(s):  
Magnetic Field ◽  
Magnetic Nanoparticles ◽  
Field Intensity ◽  
Magnetic Field Intensity ◽  
Maximum Amplitude ◽  
Target Position ◽  
Ultra Wideband ◽  
Diagnostic Reliability ◽  
Pseudo Noise ◽  
The Magnetic Field

Magnetic nanoparticles have been investigated for microwave imaging over the last decade. The use of functionalized magnetic nanoparticles, which are able to accumulate selectively within tumorous tissue, can increase the diagnostic reliability. This paper deals with the detecting and imaging of magnetic nanoparticles by means of ultra-wideband microwave sensing via pseudo-noise technology. The investigations were based on phantom measurements. In the first experiment, we analyzed the detectability of magnetic nanoparticles depending on the magnetic field intensity of the polarizing magnetic field, as well as the viscosity of the target and the surrounding medium in which the particles were embedded, respectively. The results show a nonlinear behavior of the magnetic nanoparticle response depending on the magnetic field intensity for magnetic nanoparticles diluted in distilled water and for magnetic nanoparticles embedded in a solid medium. Furthermore, the maximum amplitude of the magnetic nanoparticles responses varies for the different surrounding materials of the magnetic nanoparticles. In the second experiment, we investigated the influence of the target position on the three-dimensional imaging of the magnetic nanoparticles in a realistic measurement setup for breast cancer imaging. The results show that the magnetic nanoparticles can be detected successfully. However, the intensity of the particles in the image depends on its position due to the path-dependent attenuation, the inhomogeneous microwave illumination of the breast, and the inhomogeneity of the magnetic field. Regarding the last point, we present an approach to compensate for the inhomogeneity of the magnetic field by computing a position-dependent correction factor based on the measured magnetic field intensity and the magnetic susceptibility of the magnetic particles. Moreover, the results indicate an influence of the polarizing magnetic field on the measured ultra-wideband signals even without magnetic nanoparticles. Such a disturbing influence of the polarizing magnetic field on the measurements should be reduced for a robust magnetic nanoparticles detection. Therefore, we analyzed the two-state (ON/OFF) and the sinusoidal modulation of the external magnetic field concerning the detectability of the magnetic nanoparticles with respect to these spurious effects, as well as their practical application.

scholarly journals Study the effect of static magnetic field intensity on drug delivery by magnetic nanoparticles

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Abbas Moghanizadeh ◽  
Fakhreddin Ashrafizadeh ◽  
Jaleh Varshosaz ◽  
Antoine Ferreira
Keyword(s):  
Magnetic Field ◽  
Drug Delivery ◽  
Magnetic Nanoparticles ◽  
Ct Scan ◽  
Static Magnetic Field ◽  
Field Intensity ◽  
Magnetic Field Intensity ◽  
Micro Ct ◽  
History Of ◽  
The Magnetic Field

AbstractEmploying the magnets in therapy has a long history of treating diseases, and currently new applications such as drug delivery by magnetic nanoparticles are gaining more attention. This research tried to study the effect of static magnetic field intensity on drug delivery by magnetic nanoparticles carrying thrombolytic agents. In this research, Fe3O4@SiO2 nanoparticles carrying streptokinase were applied. The efficiency of thrombolysis and micro-CT-scan images are utilized to study the effect of different magnetic fields (0.1, 0.2, 0.3 and 0.5 T) on thrombolysis. The results confirm that increasing the static magnetic field intensity accelerated the thrombolysis. Increasing the intensity of the magnetic field from 0.1 to 0.3 T leads to an increase in clot dissolution rate from 55 to 89%, respectively. Moreover, micro-CT-scan images revealed that magnetic nanoparticles carrying a thrombolytic agent penetrated deeper into the mesh-like structure of clot as the magnetic field intensities increased, which could lead to further dissolution of the clot.

Tunable amplified spontaneous emission based on liquid magnetically responsive photonic crystals

2019 ◽  
Vol 7 (13) ◽  
pp. 3740-3743 ◽  
Author(s):  
Ying Li ◽  
Yue Long ◽  
Guoqiang Yang ◽  
Chen-Ho Tung ◽  
Kai Song
Keyword(s):  
Magnetic Field ◽  
Photonic Crystals ◽  
Spontaneous Emission ◽  
Field Intensity ◽  
Magnetic Field Intensity ◽  
Amplified Spontaneous Emission ◽  
The Magnetic Field

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

scholarly journals A Novel Method for Improving Low-Temperature Flotation Performance of Nonpolar Oil in the Molybdenite Flotation

Minerals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 609 ◽  
Author(s):  
Wan ◽  
Qu ◽  
Li ◽  
He ◽  
Bu ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Surface Tension ◽  
Low Temperature ◽  
Interfacial Tension ◽  
Field Intensity ◽  
Magnetic Field Intensity ◽  
Maximum Surface ◽  
Flotation Recovery ◽  
Flotation Performance ◽  
The Magnetic Field

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).

Viscosity of Potassium Dihydrogen Phosphate Aqueous Solution within Magnetic Field

2017 ◽  
Vol 898 ◽  
pp. 1783-1786
Author(s):  
Lei Zhang ◽  
Yi Su ◽  
Yu Lin Wu ◽  
Yao Liu ◽  
Yong Wang ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Aqueous Solution ◽  
Field Intensity ◽  
Magnetic Field Intensity ◽  
Extreme Values ◽  
Potassium Dihydrogen Phosphate ◽  
Experimental Results ◽  
Dihydrogen Phosphate ◽  
Potassium Dihydrogen ◽  
The Magnetic Field

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.

The role of the magnetic field intensity and geometry in the type III burst generation

Solar Physics ◽  
1990 ◽  
Vol 130 (1-2) ◽  
pp. 31-37 ◽  
Author(s):  
P. Zlobec ◽  
V. Ruždjak ◽  
B. Vršnak ◽  
M. Karlický ◽  
M. Messerotti
Keyword(s):  
Magnetic Field ◽  
Field Intensity ◽  
Magnetic Field Intensity ◽  
Type Iii ◽  
The Magnetic Field

Improved the Performance of Focusing Deep Hyperthermia Inductive Heating for Breast Cancer Treatment by Using Ferro-Fluid with Magnetic Shielding System

2013 ◽  
Vol 325-326 ◽  
pp. 353-358 ◽  
Author(s):  
Thosdeekoraphat Thanaset ◽  
Santalunai Samran ◽  
Thongsopa Chanchai
Keyword(s):  
Magnetic Field ◽  
Field Intensity ◽  
Magnetic Fluid ◽  
Magnetic Field Intensity ◽  
Magnetic Shielding ◽  
Inductive Heating ◽  
Surrounding Healthy Tissue ◽  
The Magnetic Field ◽  
Shielding System ◽  
Deep Hyperthermia

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.

Etude Numérique de la Section Efficace de Diffusion d'un Faisceau Laser par un Plasma en Champ Magnétique. Application à la Détermination Expérimentale de la Direction du Champ Magnétique de Confinement

1973 ◽  
Vol 51 (3) ◽  
pp. 266-276 ◽  
Author(s):  
R. L. Meyer ◽  
G. Leclert ◽  
M. Felden
Keyword(s):  
Magnetic Field ◽  
Cross Section ◽  
Field Intensity ◽  
Magnetic Field Intensity ◽  
Scattered Wave ◽  
Magnetic Field Direction ◽  
Section Efficace ◽  
Experimental Conditions ◽  
Champ Magnétique ◽  
The Magnetic Field

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.

Design and Fabrication of a Micro-Actuator Based on Electromagnetic Membrane Device

2012 ◽  
Vol 488-489 ◽  
pp. 1451-1456
Author(s):  
Rong Hua Ma ◽  
Jian Hao Zhong
Keyword(s):  
Magnetic Field ◽  
Field Intensity ◽  
Magnetic Field Intensity ◽  
Physical Size ◽  
Ac Power ◽  
Coil Structure ◽  
Electro Magnetic ◽  
Ndfeb Permanent Magnet ◽  
The Magnetic Field ◽  
A Current

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.

Comparison of the Effects of Bias Voltage and Transverse Magnetic Field on the Macro-Particles Distribution on the Surface of TiN Films Prepared by Arc Ion Plating

2011 ◽  
Vol 337 ◽  
pp. 300-306
Author(s):  
Wen Chang Lang
Keyword(s):  
Magnetic Field ◽  
Transverse Magnetic Field ◽  
Field Intensity ◽  
Magnetic Field Intensity ◽  
Transverse Magnetic ◽  
Key Factor ◽  
Influence Parameter ◽  
Two Parameters ◽  
Influence Degree ◽  
The Magnetic Field

The object of this article is to make research on the influence of transverse magnetic field and pulse bias on macro-particles on the surface of film, find the systematic law and analyze the influence law and reasons of the two parameters (transverse magnetic field and pulse bias), according to the mechanism of arc spot movement and the interaction between macro-particles and plasma. Moreover, this article aims at seeking the most important influence parameter and comparing the effect of the two parameters. Research in this paper indicates that: the key factor is the magnetic field controlled arc spot movement, because the influence of magnetic field on reducing macro-particles is much larger than bias, and the influence degree of bias on macro-particles varies with the magnetic field intensity; action of bias is obvious under the condition of low magnetic field intensity, but as the magnetic field intensity increases, its action becomes weaker and weaker; besides, purification effect of bias on particles in larger size is better than on particles in smaller size.

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