scholarly journals Erratum: “Magnetic nanoparticles with high specific absorption rate of electromagnetic energy at low field strength for hyperthermia therapy” [J. Appl. Phys. 117, 094302 (2015)]

2015 ◽  
Vol 118 (17) ◽  
pp. 179901
Author(s):  
Fridon Shubitidze ◽  
Katsiaryna Kekalo ◽  
Robert Stigliano ◽  
Ian Baker
Keyword(s):  
Magnetic Nanoparticles ◽  
Field Strength ◽  
Absorption Rate ◽  
Specific Absorption Rate ◽  
Electromagnetic Energy ◽  
Specific Absorption ◽  
Low Field ◽  
Hyperthermia Therapy

scholarly journals Specific Absorption Rate Dependency on the Co2+ Distribution and Magnetic Properties in CoxMn1-xFe2O4 Nanoparticles

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1231
Author(s):  
Venkatesha Narayanaswamy ◽  
Imaddin A. Al-Omari ◽  
Aleksandr S. Kamzin ◽  
Bashar Issa ◽  
Huseyin O. Tekin ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Field Strength ◽  
Saturation Magnetization ◽  
Absorption Rate ◽  
Specific Absorption Rate ◽  
Ferrite Nanoparticles ◽  
Cofe2o4 Nanoparticles ◽  
Specific Absorption ◽  
Octahedral Sites ◽  
Mixed Ferrite

Mixed ferrite nanoparticles with compositions CoxMn1-xFe2O4 (x = 0, 0.2, 0.4, 0.6, 0.8, and 1.0) were synthesized by a simple chemical co-precipitation method. The structure and morphology of the nanoparticles were obtained by X-ray diffraction (XRD), transmission electron microscope (TEM), Raman spectroscopy, and Mössbauer spectroscopy. The average crystallite sizes decreased with increasing x, starting with 34.9 ± 0.6 nm for MnFe2O4 (x = 0) and ending with 15.0 ± 0.3 nm for CoFe2O4 (x = 1.0). TEM images show an edge morphology with the majority of the particles having cubic geometry and wide size distributions. The mixed ferrite and CoFe2O4 nanoparticles have an inverse spinel structure indicated by the splitting of A1g peak at around 620 cm−1 in Raman spectra. The intensity ratios of the A1g(1) and A1g(2) peaks indicate significant redistribution of Co2+ and Fe3+ cations among tetrahedral and octahedral sites in the mixed ferrite nanoparticles. Magnetic hysterics loops show that all the particles possess significant remnant magnetization and coercivity at room temperature. The mass-normalized saturation magnetization is highest for the composition with x = 0.8 (67.63 emu/g), while CoFe2O4 has a value of 65.19 emu/g. The nanoparticles were PEG (poly ethylene glycol) coated and examined for the magneto thermic heating ability using alternating magnetic field. Heating profiles with frequencies of 333.45, 349.20, 390.15, 491.10, 634.45, and 765.95 kHz and 200, 250, 300, and 350 G field amplitudes were obtained. The composition with x = 0.2 (Co0.2Mn0.8Fe2O4) with saturation magnetization 57.41 emu/g shows the highest specific absorption rate (SAR) value of 190.61 W/g for 10 mg/mL water dispersions at a frequency of 765.95 kHz and 350 G field strength. The SAR values for the mixed ferrite and CoFe2O4 nanoparticles increase with increasing concentration of particle dispersions, whereas for MnFe2O4, nanoparticles decrease with increasing the concentration of particle dispersions. SARs obtained for Co0.2Mn0.8Fe2O4 and CoFe2O4 nanoparticles fixed in agar ferrogel dispersions at frequency of 765.95 kHz and 350 G field strength are 140.35 and 67.60 W/g, respectively. This study shows the importance of optimizing the occupancy of Co2+ among tetrahedral and octahedral sites of the spinel system, concentration of the magnetic nanoparticle dispersions, and viscosity of the surrounding medium on the magnetic properties and heating efficiencies.

The Adverse Effect of Electromagnetic Radiation From Cellular Base Stations in Nigeria

2021 ◽  
pp. 269-280
Author(s):  
Ndidi Stella Arinze ◽  
Patrick Uche Okafor ◽  
Osondu Ignatius Onah
Keyword(s):  
Field Strength ◽  
Radio Frequency ◽  
Electromagnetic Radiation ◽  
Mobile Phones ◽  
Absorption Rate ◽  
Specific Absorption Rate ◽  
Base Stations ◽  
Telecommunication Industry ◽  
Specific Absorption ◽  
The People

On a global scale, the telecommunication industry is experiencing tremendous growth in mobile phones. Mobile phones communicate with base stations that are erected by the telecommunication industry. The base station produces radio frequency and exposes the people near the base stations to radiation. The effect of electromagnetic radiation from four base stations located at the residential area was studied by measuring their electric field strength and calculating their magnetic field strength and power density at different distances covering a frequency range of 900MHz to 2100MHz. The obtained values showed that the four cellular base stations are operating above the standard values of the International Commission on Non-Ionizing Radiation Protection Electromagnetic Field Radiation. The specific absorption rate was measured to determine the amount of radio frequency electromagnetic radiation absorbed by the human body. The result which is in the range of 3.22-3.70 W/kg is higher than the acceptable 2 W/kg for localized specific absorption rate.

Effect of Bi Ions on the Hyperthermia Properties of Hyaluronic Acid-Coated La1−xSrxMnO3 Nanoparticles

NANO ◽  
2020 ◽  
Vol 15 (01) ◽  
pp. 2050015
Author(s):  
Lihan zheng ◽  
Yuanwei Chen ◽  
Ying Wang ◽  
Peng Wang ◽  
Tao Wang
Keyword(s):  
Hyaluronic Acid ◽  
Magnetic Nanoparticles ◽  
Curie Temperature ◽  
Absorption Rate ◽  
Specific Absorption Rate ◽  
Heating Temperature ◽  
Particle Diameter ◽  
High Energy ◽  
Average Particle ◽  
Specific Absorption

Self-regulating temperature hyperthermia based on magnetic fluid with low Curie temperature is a moderately effective method for cancer treatment. The improvement of the properties of magnetic fluids is the key for application of this method. In this paper, Bi-doped LSMO magnetic nanoparticles were synthesized using a simple sol–gel method and coated by hyaluronic acid through high energy ball milling for their possible application in self-regulating temperature hyperthermia. The crystal structure, morphology, basic magnetic properties and heating properties of these nanoparticles in a high frequency magnetic field were investigated. It was found that the hyaluronic acid-coated La[Formula: see text]Sr[Formula: see text]Bi[Formula: see text]MnO3 magnetic nanoparticles, with an average particle diameter of [Formula: see text]100[Formula: see text]nm and a Curie temperature of 48∘C, possess outstanding induction heating properties. The saturation heating temperature, specific absorption rate and effective specific absorption rate are 48∘C, 117[Formula: see text]W/g and 0.27[Formula: see text]W/g[Formula: see text]kHz[Formula: see text](kA/m2), respectively.

Elongated magnetic nanoparticles with high-aspect ratio: a nuclear relaxation and specific absorption rate investigation

2019 ◽  
Vol 21 (34) ◽  
pp. 18741-18752
Author(s):  
Matteo Avolio ◽  
Helena Gavilán ◽  
Eva Mazario ◽  
Francesca Brero ◽  
Paolo Arosio ◽  
...  
Keyword(s):  
Magnetic Nanoparticles ◽  
Aspect Ratio ◽  
Physical Properties ◽  
High Aspect Ratio ◽  
Biomedical Applications ◽  
Absorption Rate ◽  
Specific Absorption Rate ◽  
Nuclear Relaxation ◽  
Specific Absorption ◽  
Elongated Nanoparticles

High aspect-ratio elongated nanoparticles with suitable porosity present partially controlled chemico-physical properties to obtain good heating/contrast efficiency for biomedical applications.

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