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1

Synthesis and magnetic properties of Fe2O3 nanoparticles for hyperthermia application

Szmajnta K., Szindler M.M., Szindler M.

Archives of Materials Science and Engineering

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2021

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Vol. 109, nr 2

80--85

EN

Purpose: The main purpose of this publication is to bring closer co-precipitation method of magnetic particles synthesis. Procedure of examining and characterisation of those materials was also shown. Design/methodology/approach: During the work, the properties and possible biomedical application of the material produced were also examined. Surface morphology studies of the obtained particles were made using Zeiss's Supra 35 scanning electron microscope and S/TEM TITAN 80-300 transmission electron microscope. In order to confirm the chemical composition of observed layers, qualitative tests were performed by means of spectroscopy of scattered X-ray energy using the Energy Dispersive Spectrometer (EDS). The Raman spectra of the samples were measured with a InVia Raman microscope by Renishaw. Magnetic properties of hematite nanoparticles were made using VSM magnetometer. Findings: Using VSM magnetometer proved that obtained material is mixture of ferromagnetic and superparamagnetic domain. Practical implications: Magnetic Nanoparticles (MNPs) has been gaining an incrementally increasing interest of scientists in the biomedical areas. Presented materials can be used in the hyperthermia phenomena which can be used in precise cancer treatment. Originality/value: Specific magnetic properties which determinate obtained material to be well for hyperthermia phenomena.

2

On the new types of composite metamaterials

Tralle Igor, Zięba Paweł

Physics for Economy

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2019

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Vol. 3, No. 1

53-65

EN

This paper is the review of our study published in J Appl Phys 115, 233509 (2014) and J Mater Sci 53, 2034 (2018). In it, we examined the possibility of fabricating the metamaterial, which is both gyrotropic and of the simultaneously negative permittivity and permeability. Our idea was to use the three-component mixture of ingredients, where one of them is responsible for the negative effective permeability µeff of hypothetical metamaterial, while all three are responsible for the negative value of effective permittivity εeff. At first we considered the following composite: the first component was the “swarm” of single-domain ferromagnetic nanoparticles, immersed in a mixture of other two, silver and mercury cadmium telluride. Then, as fabrication of the Hg1-x Cdx Te is related to using mercury which is very poisoning, we tried to exclude this material substituting it by Pb1-x Snx Te. Additionally, taking into account that silver is relatively expensive material, we have also used Cu and Al particles as the cheaper substitute of it. We have shown by computer simulations that by the proper fitting of the parameters, e.g., the radius of nanoparticles, their magnetic moments, the relative concentration of ingredients, etc., it is possible to obtain the double-negative metamaterial, that is with negative refraction index in a relatively broad range of temperatures and magnetic fields. The last seems to be very promising in terms of practical applications of metamaterials.

PL

Praca stanowi przegląd prac autorów, opublikowanych wcześniej (J Appl Phys 115, 233509 (2014) oraz J Mater Sci 53, 2034 (2018)). W w/w pracach autorzy zbadali możliwość utworzenia metamateriału, który byłby jednocześnie giroskopowy oraz posiadał ujemne części rzeczywiste przenikalności magnetycznej i dielektrycznej. Ideą jest wykorzystanie w tym celu mieszanki trzech składników, z których pierwszy - to "rój" ferromagnetycznych nanocząstek.

3

Contribution of planetary electronic structure of atom to molecular interaction and properties of nanocomposites

Sikoń Marek, Bidzinska E., Marcinowski J.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2019

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Vol. 67, nr 1

77--89

EN

The paper proposes a study of molecular interactions using the planetary model of the atomic structure. The description refers to transfer of the interactions by electrons bonded with an atom in a planetary system. In molecules we refer to analysis of electrons that remain unpaired during the formation of chemical compounds. The planetary electronic state of molecular interactions is defined by considering the action arm for interatomic forces. Then the interaction torque is defined. The problem is studied in a collection of atoms forming a nanoparticle and then analysis is carried on in the entire volume of the nanocomposite, which is defined as a set of the nanoparticles in a field of matrix-nanofiller interactions. As a result, new mechanical, magnetic, and optical properties of the nanocomposite arise and are described herein. The atomic-scale phenomena are described by both classical and quantum mechanics and are then transferred to the nanoparticle scale by applying statistical mechanics. The quantum solutions for the optically active electrons form the basis for the optical properties of the nanocomposite using forced gyrobirefringence and Maxwell equations. The results of the theoretical analysis are confirmed by experiment using an electron paramagnetic resonance spectrometer.

4

Nano-structured (Mo,Ti)C-C-Ni magnetic powder

Kaczmarek S. M., Biedunkiewicz A., Bodziony T., Figiel P., Skibiński T., Krawczyk M., Gabriel-Półrolniczak U.

Journal of Achievements in Materials and Manufacturing Engineering

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2018

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Vol. 86, nr 1

5--13

EN

Purpose: The paper presents the results of phase composition and magnetic properties of Mo-Ni-Ti-C nanostructured powders. The aim of this research is understanding the correlation between key magnetic properties and the parameters that influence them in the nanostructured powders from Mo-Ni-Ti-C system. Design/methodology/approach: The powder samples were synthesised using modified sol-gel method. Obtained powder were subjected for composition and magnetic properties in a wide temperature range by means of Electron Paramagnetic Resonance (EPR) and magnetic susceptibility measurements. To study the phase composition X-ray diffraction were performed. The morphology of the powders were investigated by scanning electron microscopy (SEM). Findings: Different kinds of structural and magnetic phases have been found in the investigated compounds, e.g. (Mo, Ti)C, C, Ni. It was found that such different phases create different kinds of magnetic interactions, from paramagnetic, antiferromagnetic up to superparamagnetic. Significant magnetic anisotropy has been revealed for low temperatures, which lowers with temperature increase. Moreover, non-usual increasing of the magnetization as a function of temperature was observed. It suggests, that overall longrange AFM interaction may be responsible for the magnetic properties. Research limitations/implications: For the future work explanation which phases in Mo-Ni-Ti-C system are responsible for different kinds of magnetic interactions are planned. Practical implications: The composition of different kinds of phases may be controlled to tune magnetic properties of the nanostructured Mo-Ni-Ti-C systems. Originality/value: In this study, for the first time Mo-Ni-Ti-C nanostructured samples were prepared with different kinds of structural and magnetic phases, creating different kinds of magnetic interactions, from paramagnetic, antiferromagnetic up to superparamagnetic-like. The latter seems to be formed due to the presence of magnetic nanoparticles and longrange antiferromagnetic interactions dominating in the whole temperature range.

5

Preparation and characterization of La- and Ni-doped magnetite nanoparticles

Ma J., Ji Y., Tian M.

Materials Science Poland

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2009

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Vol. 27, No. 4/1

981--986

EN

La- and Ni-doped Fe3O4 nanocomposite particles with a high saturation magnetization were prepared by a homogeneous precipitation method in aqueous solutions. The obtained nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), inductively-coupled plasma atomic emission spectroscopy (ICPAES) and vibrating sample magnetometry (VSM). The results showed the diameters of La- or Ni-doped Fe3O4 composite particles to be in the range of 10-25 nm. The specific saturation magnetization of La- or Ni-doped Fe3O4 was considerably higher than that of pure Fe3O4 nanoparticles. The nanocomposite particles exhibited superparamagnetic behaviour.

6

Magnetic properties of cementite (Fe3C) nanoparticle agglomerates in a carbon matrix

Lipert K., Kaźmierczak J., Pełech I., Narkiewicz U., Ślawska-Waniewska A., Lachowicz H. K.

Materials Science Poland

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2007

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Vol. 25, No. 2

399--404

EN

Magnetic properties of two FeC samples with different amounts of carbon have been studied. In both cases, the amount of carbon was well above the mass sufficient to transform nanocrystalline iron into iron carbide (cementite). Through the dc magnetic and transmission electron microscopy (TEM) measurements it was shown that cementite nanoparticles formed agglomerates; the size distribution of these nanoparticles was very wide, and superparamagnetic-like behaviour was not observed even at room temperature.

7

Fulereny modyfikowane metalami przejściowymi z grupy żelazowców

Kowalska E., Byszewski P., Radomska J.

Elektronika : konstrukcje, technologie, zastosowania

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2002

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Vol. 43, nr 12

49-52

PL

Przedstawiono metody domieszkowania fulerytu metalami przejściowymi: Fe, Co i Ni z wykorzystaniem metalocenów tych pierwiastków: ferrocenu (Fn), kobaltocenu (Cn), niklocenu (Nn). W wyniku reakcji fulerenu z kobaltocenem i niklocenem otrzymano związki C60Cn3 oraz C60Nn6 i C60Nn. W celu syntezy adduktów C60: Fn zastosowano HNO3, AlCl3 i pochodną ferrocenu FnCNO. Termiczny rozkład adduktów C60: Fn i C60: Cn prowadzi do wytworzenia fulerytów C60Fe i C60Co3 o strukturze fcc z atomami metali zdyspergowanymi pomiędzy molekułami fulerenów w sieci krystalicznej.

EN

The methods on preparation of fullerites with transition metals Fe, Co and Ni using ferrocene (Fn), cobaltocene (Cn) and nickelocene (Nn) are presented. The samples of the composition C60Cn3, C60Nn6, C60Nn were obtained directly in the reactions. In order to synthesize the adducts C60: Fn we applied: HNO3, AICI3 and the ferrocene derivative - FnCNO. Fullerites C60Fe and C60CO3 with the fcc structure with the metal atoms dispersed between fullerenes were prepared as a result of thermal decomposition of C60: Fn and C60: Cn. Temperature and magnetic field dependence of magnetization of C60Fe and C60Co3 samples point to their superparamagnetic properties. Móssbauer spectroscopy indicates that iron may exist in two different states in the C60Fe sample, which can be caused by the Fe atom migration over the C60 molecule and diffusion between fullerenes at elevated temperature.