Magnetic properties of ultrasmall iron oxide nanoclusters in a polymer matrix

The article describes the synthesis of composite sorbents by immobilizing iron oxide in a polymer matrix with subsequent hydrothermal treatment at a temperature of 175 °C. The sorbents based on magnetite and hematite were synthesized, their magnetic properties and phase composition were evaluated, and the iron content was determined. Sorption characteristics of the composites towards microconcentrations of Sr-90 radionuclide in solutions with different mineralization and pH were investigated. It was shown that the sorbent based on magnetite was the most efficient. In alkaline media with pH above 11, the composite sorbent based on magnetite exhibited increased selectivity towards Sr-90 and proved to be suitable for application under dynamic sorption conditions with subsequent desorption of the radionuclide with a solution of HNO3.

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Complexes of copper(II) and nickel(II) with a Schiff base bonded to a polymeric support

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19832021 ◽

1983 ◽

Vol 48 (7) ◽

pp. 2021-2027 ◽

Cited By ~ 9

Author(s):

Eliška Kálalová ◽

Olga Populová ◽

Štěpánka Štokrová ◽

Pavel Stopka

Keyword(s):

Magnetic Properties ◽

Schiff Base ◽

Coordination Sphere ◽

Polymer Matrix ◽

Glycidyl Methacrylate ◽

Epr Spectra ◽

Polymeric Support ◽

Tetrahedral Configuration ◽

Paramagnetic Complexes

Copper(II) and nickel(II) ions were bonded in complexes of salicylideneimine type on a glycidyl methacrylate-ethylenedimethacrylate copolymer. The geometry of the complexes on the polymer was studied by measuring their magnetic properties, EPR spectra, and ultraviolet-visible spectra.Only paramagnetic complexes possessing a pseudo-tetrahedral configuration were found. The effect of the polymer matrix and of the immobility of the bonded Schiff base on the distortion of the coordination sphere of the central ion is discussed.

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Reversible magnetism switching of iron oxide nanoparticle dispersions by controlled agglomeration

Nanoscale Advances ◽

10.1039/d1na00159k ◽

2021 ◽

Author(s):

Stephan Müssig ◽

Björn Kuttich ◽

Florian Fidler ◽

Daniel Haddad ◽

Susanne Wintzheimer ◽

...

Keyword(s):

Magnetic Properties ◽

Iron Oxide ◽

Light Scattering ◽

Superparamagnetic Iron Oxide ◽

Iron Oxide Nanoparticle ◽

Oxide Nanoparticles ◽

X Ray ◽

X Ray Scattering ◽

Nanoparticle Dispersions ◽

Oxide Nanoparticle

The controlled agglomeration of superparamagnetic iron oxide nanoparticles (SPIONs) was used to rapidly switch their magnetic properties. Small-angle X-ray scattering (SAXS) and dynamic light scattering showed that tailored iron oxide...

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Properties of Silicone Rubber-Based Composites Reinforced with Few-Layer Graphene and Iron Oxide or Titanium Dioxide

Polymers ◽

10.3390/polym13101550 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1550

Author(s):

Vineet Kumar ◽

Anuj Kumar ◽

Minseok Song ◽

Dong-Joo Lee ◽

Sung-Soo Han ◽

...

Keyword(s):

Magnetic Properties ◽

Titanium Dioxide ◽

Iron Oxide ◽

Stress Relaxation ◽

Silicone Rubber ◽

Room Temperature ◽

Relaxation Rates ◽

Layer Graphene ◽

Few Layer Graphene ◽

Mechanical Actuation

The increasing demand for polymer composites with novel or improved properties requires novel fillers. To meet the challenges posed, nanofillers such as graphene, carbon nanotubes, and titanium dioxide (TiO2) have been used. In the present work, few-layer graphene (FLG) and iron oxide (Fe3O4) or TiO2 were used as fillers in a room-temperature-vulcanized (RTV) silicone rubber (SR) matrix. Composites were prepared by mixing RTV-SR with nanofillers and then kept for vulcanization at room temperature for 24 h. The RTV-SR composites obtained were characterized with respect to their mechanical, actuation, and magnetic properties. Fourier-transform infrared spectroscopy (FTIR) analysis was performed to investigate the composite raw materials and finished composites, and X-ray photoelectron spectroscopy (XPS) analysis was used to study composite surface elemental compositions. Results showed that mechanical properties were improved by adding fillers, and actuation displacements were dependent on the type of nanofiller used and the applied voltage. Magnetic stress-relaxation also increased with filler amount and stress-relaxation rates decreased when a magnetic field was applied parallel to the deformation axes. Thus, this study showed that the inclusion of iron oxide (Fe3O4) or TiO2 fillers in RTV-SR improves mechanical, actuation, and magnetic properties.

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Induction of Axonal Outgrowth in Mouse Hippocampal Neurons via Bacterial Magnetosomes

International Journal of Molecular Sciences ◽

10.3390/ijms22084126 ◽

2021 ◽

Vol 22 (8) ◽

pp. 4126

Author(s):

Sara De Vincentiis ◽

Alessandro Falconieri ◽

Frank Mickoleit ◽

Valentina Cappello ◽

Dirk Schüler ◽

...

Keyword(s):

Magnetic Properties ◽

Iron Oxide ◽

Hippocampal Neurons ◽

Magnetotactic Bacteria ◽

Oxide Nanoparticles ◽

Axonal Outgrowth ◽

Mechanical Forces ◽

Internalization Process ◽

Oxide Crystals ◽

Stimulation Of

Magnetosomes are membrane-enclosed iron oxide crystals biosynthesized by magnetotactic bacteria. As the biomineralization of bacterial magnetosomes can be genetically controlled, they have become promising nanomaterials for bionanotechnological applications. In the present paper, we explore a novel application of magnetosomes as nanotool for manipulating axonal outgrowth via stretch-growth (SG). SG refers to the process of stimulation of axonal outgrowth through the application of mechanical forces. Thanks to their superior magnetic properties, magnetosomes have been used to magnetize mouse hippocampal neurons in order to stretch axons under the application of magnetic fields. We found that magnetosomes are avidly internalized by cells. They adhere to the cell membrane, are quickly internalized, and slowly degrade after a few days from the internalization process. Our data show that bacterial magnetosomes are more efficient than synthetic iron oxide nanoparticles in stimulating axonal outgrowth via SG.

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Magnetic properties of FeCo-iron oxide core–shell nanoparticles investigated through first order reversal studies

Applied Physics A ◽

10.1007/s00339-020-04176-z ◽

2021 ◽

Vol 127 (1) ◽

Author(s):

G. Antilen Jacob ◽

R. Justin Joseyphus

Keyword(s):

Magnetic Properties ◽

Iron Oxide ◽

Core Shell ◽

Shell Nanoparticles ◽

First Order ◽

Iron Oxide Core ◽

Core Shell Nanoparticles

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Comparative study on the magnetic properties of iron oxide nanoparticles loaded on mesoporous silica and carbon materials with different structure

Microporous and Mesoporous Materials ◽

10.1016/j.micromeso.2009.01.029 ◽

2009 ◽

Vol 121 (1-3) ◽

pp. 178-184 ◽

Cited By ~ 27

Author(s):

Sher Alam ◽

Chokkalingam Anand ◽

Radhakrishnan Logudurai ◽

Veerappan V. Balasubramanian ◽

Katsuhiko Ariga ◽

...

Keyword(s):

Magnetic Properties ◽

Iron Oxide ◽

Mesoporous Silica ◽

Comparative Study ◽

Iron Oxide Nanoparticles ◽

Carbon Materials ◽

Oxide Nanoparticles

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Photo-fluorescent and magnetic properties of iron oxide nanoparticles for biomedical applications

Nanoscale ◽

10.1039/c5nr01538c ◽

2015 ◽

Vol 7 (18) ◽

pp. 8209-8232 ◽

Cited By ~ 99

Author(s):

Donglu Shi ◽

M. E. Sadat ◽

Andrew W. Dunn ◽

David B. Mast

Keyword(s):

Magnetic Properties ◽

Iron Oxide ◽

Physical Properties ◽

Iron Oxide Nanoparticles ◽

Basic Science ◽

Biomedical Applications ◽

Oxide Nanoparticles ◽

Nanometer Range

Iron oxide exhibits fascinating physical properties especially in the nanometer range, not only from the standpoint of basic science, but also for a variety of engineering, particularly biomedical applications.

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