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1

Operating characteristics of bearings with magnetic nanoparticles doped lubricant

Krenicky Tibor, Mascenik Jozef, Coranic Tomas, Ruzbarsky Juraj

Mining Machines

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2023

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vol. 41, iss. 3

168--174

EN

The main aim of the presented research was to investigate theoperational characteristics of a bearing when alternative lubricants were used for comparison with a standard lubricant, including that containing magnetic nanoparticles. The bearing was subjected to varying operating conditions, differing in terms of mechanical load status. The monitoring of the bearing operation parameters primarily focused on monitoring the velocity and acceleration of vibrations, as well as the operating temperature of the bearing. Thebearingwith lubricant doped by magnetic nanoparticles exhibited reduced vibration velocity and acceleration values both under no load conditions and when subjected to a mechanicalload. The operating temperature slightly increased during testing in the case ofthe bearing with nanoparticles compared to the bearing using the original lubricant.

2

Decontamination of Metronidazole Antibiotic: A Novel Nanocomposite-Based Strategy

Mhemid Rasha Khalid Sabri, Saeed Liqaa I., Shihab Mohammed Salim

Journal of Ecological Engineering

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2023

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Vol. 24, nr 9

246--259

EN

In this study, the synthesis of magnetic nanoparticles (MNPs) employing leaf extract from Alocasiamacrorrhiza was investigated as a reducing agent. CuFe2O4, CuFe2O4/CuO, and CuFe2O4/CuO/CdS made constituted the coreshell of these MNPs, which were stabilized on naturally Ninevite rocks (NRs) to provide a more cost-effective support. Analytical techniques of various methods were used to characterize the MNPs/NR nanocomposite that was produced utilizing eco-friendly methods. Among the methods used were infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and vibrating sample magnetometry (VSM). The antibiotic Metronidazole (MET) was broken down using a potent nanocatalyst made of MNPs in a solar-irradiated batch system. A solar-photocatalytic system was used to investigate the effects of the initial MET concentration, irradiation time, H2O2 concentration, catalyst nanocomposite concentration, and pH solution on MET photodegradation. Artificial neural networks (ANNs) were also used in data modeling to determine which oxidation technique performed the best in certain conditions. This investigation showed that the CuFe2O4/CuO/CdS magnetic catalyst had the greatest MET removal efficiency of 97% among all MNPs. Moreover, ANN were used to examine data from the photocatalytic oxidation of MET utilizing a CuFe2O4/CuO/CdS/NRs catalyst. The results revealed that the MNP dose had the highest influence on the photodegradation of MET. The correlation coefficients (R2) for the training regressions, validation, testing, and total data were all 0.999, 0.996, 0.993, and 0.998, respectively.

3

Impact of Nanoparticles on Biogas Production from Anaerobic Digestion of Sewage Sludge

Heikal Ghada, Shakroum Mohamed, Vranayova Zuzana, Abdo Ahmed

Journal of Ecological Engineering

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2022

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Vol. 23, nr 8

222--240

EN

Since anaerobic digestion (AD) is the preferred procedure for sludge treatment and disposal, it is constrained by the hydrolysis and acidogenesis stages. Nanomaterials have an impact on the AD process due to their unique properties (large specific surface areas, solubility, adsorption reduction of heavy metals, degradation of organic matter, reduction of hydrogen supplied and catalytic nature) which make them advantageous in many applications due to their effectiveness in improving the AD efficiency. Magnetic Nanoparticles (MNPs) were used in the present study to improve the biogas production. The experiments were divided into two stages to evaluate the effect of adding MNPs to two types of sewage sludge (SS): attached growth process (AG) and activated sludge (AS). The first stage consists of 15 tests divided into three experiments (A, B, and C). Doses of MNPs (20, 50, 100, 200) mg/l were added to all digesters in the same experiment except for one digester (the control). Experiments A, B and C achieved the highest biogas production when 100 mg/l of MNPs was added. They were 1.9, 1.93 and 2.07 times higher than the control for A, B and C respectively. The second stage consists of 12 tests with a pretreatment for some of SS. It was divided into two experiments (D, E), where the chemical pretreatment was applied to experiment D and the thermal pretreatment was applied to experiment E except for the control. For digester D4, which had 100 mg/l of MNPs after a chemical pretreatment at pH = 12, the biogas production increased by 2.2 times higher than the control (D0) and 1.5 times higher than the untreated sludge with the addition of 100 mg/l MNPs (DN). Thermal pretreatment at 100 °C with addition of 100 mg/l MNPs (E4) achieved a biogas yield 2 times higher than the control (E0), and 1.39 times higher than untreated sludge with 100 mg/l MNPs (EN). The previous results indicate that the integration of magnetite can serve as the conductive materials, promoting inherent indirect electron transfer (IET) and direct interspecies electron transfer (DIET) between methanogens and fermentative bacteria which lead to a more energy-efficient route for interspecies electron transfer and methane productivity. This study demonstrated the positive effect of magnetite on organic biodegradation, process stability and methane productivity.

4

Otrzymywanie, zastosowanie oraz modyfikacje nanocząstek magnetycznych

Okrzesik Mateusz, Piątek Artur, Drabczyk Anna

Inżynieria Materiałowa

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2022

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Vol. 43, nr 1

10--17

PL

Przedstawiono informacje na temat wytwarzania, modyfikacji oraz zastosowania nanocząstek magnetycznych (MnPS). Nanocząstki (nP) ze względu na duży stosunek objętości do powierzchni oraz małe wymiary wykazują odmienne właściwości w porównaniu z innymi materiałami o rozmiarach większych, np. mikrometrycznych. W pracy przedstawiono kilka metod wytwarzania MnPS, takich jak metoda współstrącania, metoda odwróconych miceli, metoda wykorzystująca ekstrakt z wodorostu Kappaphycus alvarezii czy metoda wykorzystująca bakterie magnetotaktyczne do produkcji nanocząstek magnetycznych. W rozdziale opisującym metody modyfikacji tychże struktur zawarto informacje na temat pokrywania nanocząstek kwasem oleinowym oraz o metodzie Langmuira i Blodgetta umożliwiającej formowanie filmów i nanocząstek na podłożach fazy stałej. Nanocząstki magnetyczne znajdują szerokie zastosowanie w nauce, ale szczególną rolę odgrywają w medycynie, gdzie dzięki unikalnym właściwościom magnetycznym możliwe jest ich wykorzystanie do kontrastowania w obrazowaniu za pomocą rezonansu magnetycznego, leczenia hipertermią magnetyczną, naprawy tkanek czy dostarczania leków w sposób kontrolowany do określonego miejsca w organizmie.

EN

The presented publication provides information on the fabrication, modification and application of magnetic nanoparticles. Nanoparticles, due to their large volume to surface area ratio and small size, exhibit different properties compared to other materials with larger sizes such as micrometers. In our work, we have presented several methods to produce magnetic nanoparticles (MnPS) such as co-precipitation method, inverted micelle method, method using Kappaphycus alvarezii seaweed extract or method using magnetotactic bacteria to produce magnetic nanoparticles. In the chapter describing methods for modifying these structures, we include information on coating nanoparticles with oleic acid and on the Langmuir-Blodgett method for forming films and nanoparticles on solid phase substrates. Magnetic nanoparticles are widely used in science, however, they play a special role in medicine, where due to their unique magnetic properties it is possible to use them for contrast in magnetic resonance imaging, magnetic hyperthermia treatment, tissue repair or drug delivery in a controlled manner to a specific location in the body.

5

Nanocząstki magnetyczne w diagnostyce i leczeniu chorób nowotworowych

Piech Radosław, Skrzypiec Maksymilian, Drabczyk Anna

Inżynieria Materiałowa

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2021

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Vol. 42, nr 6

15--23

PL

W ostatnich latach intensywnie bada się nanocząstki magnetyczne (MNPs) pod względem użycia ich w medycynie, głównie w walce z chorobami nowotworowymi. Przy użyciu nanocząstek magnetycznych możliwe jest celowe, nieinwazyjne dostarczenie leku w miejsce kumulacji komórek rakowych za pomocą m.in. pola magnetycznego, co faworyzuje je w stosunku do klasycznych cytostatyków, które uszkadzają również zdrowe komórki i oddziałują na cały organizm. Nanocząstki magnetyczne mogą służyć również do wykrycia i zdiagnozowania chorób nowotworowych, jak również określania postępów terapii antynowotworowej. Różnorodność zastosowania nanocząstek magnetycznych sprawia, że są one postrzegane jako innowacyjny i przełomowy środek do zwalczania chorób nowotworowych. W artykule zebrano informacje na temat najpopularniejszych metod wytwarzania nanocząstek magnetycznych i ich wykorzystania w medycynie oraz poruszono kwestię biokompatybilności i toksyczności tychże struktur.

EN

Magnetic nanoparticles have attracted attention because of their properties that make it possible to use them to treat cancer through targeted therapy. By using a magnetic field to target nanoparticles containing drugs, it is possible to reach cancer cells directly and fight them in their place of growth without affecting healthy cells or the body as a whole. Magnetic nanoparticles can be used in diagnostics to detect and diagnose cancer as well as to determine the progress of anti-cancer therapy. In this paper, we mentioned the biocompatibility and toxicity of magnetic nanoparticles because their use also carries the risk of health damage which is a necessity for further research on this topic.

6

Ultrasonic specific absorption rate in nanoparticle-mediated moderate hyperthermia

Gambin Barbara, Kruglenko Eleonora

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2021

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Vol. 69, nr 3

art. no. e137053

EN

Magnetic nanoparticle’s different applications in nanomedicine, due to their unique physical properties and biocompatibility, were intensively investigated. Recently, Fe₃O₄ nanoparticles, are confirmed to be the best sonosensitizers to enhance the performance of HIFU (high intensity focused ultrasound). They are also used as thermo-sensitizers in magnetic hyperthermia. A new idea of dual, magneto-ultrasound, coupled hyperthermia allows the ultrasound intensity to be reduced from the high to a moderate level. Our goal is to evaluate the enhancement of thermal effects of focused ultrasound of moderate intensity due to the presence of nanoparticles. We combine experimental results with numerical analysis. Experiments are performed on tissue-mimicking materials made of the 5% agar gel and gel samples containing Fe₃O₄ nanoparticles with φ = 100 nm with two fractions of 0.76 and 1.53% w/w. Thermocouples registered curves of temperature rising during heating by focused ultrasound transducer with acoustic powers of the range from 1 to 4 W. The theoretical model of ultrasound-thermal coupling is solved in COMSOL Multiphysics. We compared the changes between the specific absorption rates (SAR) coefficients determined from the experimental and numerical temperature rise curves depending on the nanoparticle fractions and applied acoustic powers.We confirmed that the significant role of nanoparticles in enhancing the thermal effect is qualitatively similarly estimated, based on experimental and numerical results. So that we demonstrated the usefulness of the FEM linear acoustic model in the planning of efficiency of nanoparticle-mediated moderate hyperthermia.

7

A numerical investigation into the magnetic nanoparticles hyperthermia cancer treatment injection strategies

Dahaghin Ali, Emadiyanrazavi Seyedhamidreza, Salimibani Milad, Bahreinizad Hossein, Haghpanahi Mohammad, Eivazzadeh-Keihan Reza, Maleki Ali

Biocybernetics and Biomedical Engineering

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2021

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Vol. 41, no. 2

516--526

EN

Magnetic nanoparticles hyperthermia is a new and promising cancer treatment method. Injection strategies are one of the determining factors in the success of the treatment. This study is a numerical investigation into the injection methods of MNPs hyperthermia. In order to have a realistic tumor morphology and vascularity, a model of Lower Limb tumor was constructed from the CT images. The finite element method was used to solve the problem. This study includes fluid flow in capillaries and inside the porous tissue of the tumor, mass transfer from the capillaries into the tumor tissue, inside the tumor tissue, and from the tumor tissue into the capillaries, and finally heat transfer across the tumor. Finally, tissue damage was calculated in order to evaluate the performance of each method. Results of intravenous injection with single point intratumoral injections were compared here. The results of this study show that intravenous injection yields more homogenous MNPs concentration and temperature distribution, while MNPs concentration and temperature increase in direct injection was limited in a small area around the injection point. Results of the current research suggest that damage to tissue from the hyperthermia with intravenous injection is much more significant compared to direct injection.

8

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.

9

Synthesis of α-Fe2O3 nanoparticles and analyzing the effect of annealing temperature on its properties

Thimmiah Bhargavi Ram, Nallathambi Gobi

Materials Science Poland

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2020

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Vol. 38, No. 1

116--121

EN

α-Fe2O3 nanoparticles were synthesized via co-precipitation technique using ferric and ferrous salts and potassium hydroxide as precipitation agents. The samples were calcined at 350 °C, 550 °C and 750 °C for 3 hours. The obtained iron oxide was characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and dynamic light scattering (DLS). Crystallinity of the sample was studied by X-ray diffraction. SEM micrographs showed nonuniform size distribution of the particles forming agglomerates. TGA analysis revealed trace amount of weight loss and material stability for the samples calcined at temperatures above 500 °C. DLS results indicated that increasing of annealing temperature resulted in reduction of the particle size and more uniform size distribution. At the maximum annealing temperature of 750 °C, the mean diameter of the particles of 100 nm was observed.

10

Synthesis, electrical and magnetic properties of polymer coated magnetic nanoparticles for application in MEMS/NEMS

Javid Muhammad Arshad, Sajjad Muhammad, Ahmad Saeed, Khan Muhammad Azhar Shahid, Nadeem Khalid, Amin Niama, Mehmood Zahid

Materials Science Poland

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2020

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Vol. 38, No. 4

553--558

EN

In this research work, polymer coated magnetic nanoparticles were prepared by co-precipitation method. The samples were characterized by XRD, SEM, EDS, VSM and two probe DC conductivity measurements. XRD pattern indicated the existence of a sole cubic phase of Fe3O4 with Miller indices (2 2 0), (3 1 1), (5 1 1), (4 4 0). An average size of magnetic nanoparticles was about 22.9 nm and it was reduced to 21.3 nm and 19.4 nm after 1 wt. %. and 2 wt. % coating of PEG-6000, respectively. The morphology and size of the samples were investigated by scanning electron microscope (SEM). EDX spectra confirmed the coating of PEG on magnetic nanoparticles. Magnetic properties were examined by vibrating sample magnetometer (VSM). Saturation magnetization (Ms) decreased as the concentration of PEG increased in the magnetic material. Electrical properties of uncoated and polymer coated Fe3O4 nanoparticles were studied by two-probe conductivity meter. This study concluded that the thermal flow of charge in polymer coated magnetic nanoparticles can be evaluated at micro and nano level.

11

Polystyrene/magnetite nanocomposite synthesis and characterization: investigation of magnetic and electrical properties for using as microelectromechanical systems (MEMS)

Omidi M. H., Alibeygi M., Piri F., Masoudifarid M.

Materials Science Poland

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2017

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Vol. 35, No. 1

105--110

EN

In this work, a novel polystyrene/Fe3O4 nanocomposite prepared by in-situ method is presented. Magnetic Fe3O4 nanoparticles were encapsulated by polystyrene. The FT-IR spectra confirmed polystyrene/ Fe3O4 nanocomposite preparation. The electrical properties of prepared nanocomposite were investigated by cyclic voltammetry (CV). The CV analysis showed good electrical conductivity of the synthesized nanocomposite. Magnetic properties of the nanocomposite were studied by vibrating sample magnetometer (VSM). The VSM analysis confirmed magnetic properties of the nanocomposite. The morphology and the size of the synthesized nanocomposite were investigated by field emission scanning electron microscope (FESEM). According to the VSM and CV results, such nanocomposite can be used in microelectromechanical systems.

12

Application of magnetic nanoparticles for water treatment

Marcinkowska D.

Technical Issues

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2016

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nr 2

33--38

EN

In this study magnetic nanoparticles were fabricated and used for water treatment. Nanoparticles were prepared in two ways. The first one involved NiZn ferrite nanoparticles synthesized by co-precipitation of metal cations with sodium hydroxide at high temperature. The second one featured maghemite nanoparticles was prepared by salt-assisted solid-state reaction. Modification and functionalization of nanoparticles surface was investigated. Nanoparticles were characterized by scanning electron microscopy (SEM). Modified nanoparticles were added to the solution of desired concentration of methylene green. Adsorption ability was examined trough ultraviolet-visible spectroscopy (UV-VIS). For NiZn ferrite and also for maghemite nanoparticles results were positive. Both of complexes can be used for water treatment with 51% success for maghemite and 72% for NiZn ferrite nanoparticles.

13

Experimental investigation on heat transfer rate of Co–Mn ferrofluids in external magnetic field

Margabandhu M., Sendhilnathan S., Senthilkumar S., Hirthna K.

Materials Science Poland

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2016

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Vol. 34, No. 2

427--436

EN

Manganese substituted cobalt ferrite (Co1–xMnxFe2O4 with x = 0, 0.3, 0.5, 0.7 and 1) nanopowders were synthesized by chemical coprecipitation method. The synthesized magnetic nanoparticles were investigated by various characterization techniques, such as X-ray diffraction (XRD), vibrating sample magnetometry (VSM), scanning electron microscopy (SEM) and thermogravimetric and differential thermal analysis (TG/DTA). The XRD results confirmed the presence of cubic spinel structure of the prepared powders and the average crystallite size of magnetic particles ranging from 23 to 45 nm. The VSM results showed that the magnetic properties varied with an increase in substituted manganese while SEM analysis showed the change in the morphology of obtained magnetic nanoparticles. The TG/DTA analysis indicated the formation of crystalline structure of the synthesized samples. The heat transfer rate was measured in specially prepared magnetic nanofluids (nanoparticles dispersed in carrier fluid transformer oil) as a function of time and temperature in presence of external magnetic fields. The experimental analysis indicated enhanced heat transfer rate of the magnetic nanofluids which depended upon the strength of external magnetic field and chemical composition.

14

Understanding of the role of pH in filling mesoporous silica with magnetic nanoparticles

Wolak W., Dudek M. R., Ho D. Q., Marcjan K.

Journal of Applied Mathematics and Computational Mechanics

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2016

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Vol. 15, nr 1

191--196

EN

Computer simulation study of filling pores of mesoporous silica with magnetic iron oxide nanoparticles which are diffusing towards the silica surface from a water solution with a given pH was presented. Three different values of the pH of the solution were under consideration, pH = 4, 7, and 10. The size of nanoparticles was of the order of magnitude of the nanopore diameter. It was observed that in the case of a low concentration of magnetic nanoparticles in the water solution the process of filling the silica pores weakly depends on the pH of the solution. The value of pH becomes only relevant for large concentration of magnetic nanoparticles. In the simulation, a 2-state Potts model was used for preparing the silica matrix. Diffusion of magnetic nanoparticles was restricted to lattice sites only.

15

Nanocząstki magnetytu powlekane polimerami do zastosowań biomedycznych. Cz. II. Nanocząstki Fe3O4 z powłokami z polimerów syntetycznych

Chełminiak D., Ziegler-Borowska M., Kaczmarek H.

Polimery

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2015

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T. 60, nr 2

87--94

PL

Artykuł jest drugą częścią przeglądu literatury dotyczącej nanocząstek magnetytu stosowanych w biologii i medycynie. Omówiono układy nanocząstek Fe3O4 z powłokami z polimerów syntetycznych, m.in. z poliwinylopirolidonu, poli(glikolu etylenowego), polidopaminy. Przedstawiono przykłady trójskładnikowych układów magnetytu ze związkami krzemu, stabilizowanych polimerami.

EN

This article is a second part of literature review concerning magnetite nanoparticles used in biology and medicine. Fe3O4 nanoparticles coated by synthetic polymers such as polyvinylpyrrolidone, poly(ethylene glycol) and polydopamine are described. Examples of trilayer hybrids composed of magnetite, silicon compound and polymer are also presented. Particular attention is paid to biological and medical applications of polymers containing magnetic nanoparticles as contrast agents for magnetic resonance imaging, drug delivery systems, compounds used in separation techniques and in hyperthermic anticancer therapy.

16

Main measurement and automation nodes of magnetic nanoparticles heater: student project

Samchenko R. P

International Journal of Microelectronics and Computer Science

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2014

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Vol. 5, nr 1

35--40

EN

At carrying out the experiments to determine the losses for heating of magnetic nanoparticles (MNP) and composites on their basis, which are commonly used in the cancer treatment, it is necessary to reduce the number of manually regulated processes, e.g.: frequency change and resonance adjustment, alternating magnetic field strength amplitude change, as well as the measurements. In present article structural diagram of device for such purposes with improved automation level is presented and circuit engineering solutions for main measurement and automation nodes are proposed. There is an attempt to perform a purely electronic control of current ﬂowing through the heating solenoid coil to adjust the magnetic field strength applied to the MNP sample without using any additional power electronics components.

17

Magnetic core-shell structures as potential carriers in drug delivery system

Łuszczyk K.

Interdisciplinary Journal of Engineering Sciences

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2014

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Vol. 2, no. 1

1--4

EN

Magnetic core-shell structures have a high potential for promising application in biomedicine as drug carriers. In this paper, magnetic core-shell structure obtained by the sol-gel method was presented. In order to provide the protective coating of magnetic MnFe2O4 nanoparticles, amorphous silica was used. It has been shown that magnetic core was successfully encapsulated in SiO2 matrix and that the received core-shell material had magnetic properties.

18

Chemical preparation of core - shell nanoparticles

Kalska-Szostko B., Wykowska U., Basa A., Szymański K.

Nukleonika

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2013

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Vol. 58, No. 1

35-38

EN

Nanoparticles obtained during layer-by-layer chemical deposition have been obtained. The particles diameter varied between 5 nm and 9 nm and can be tuned by changing molarity of the synthesis ingredients. The intention was the creation of copper or iron oxide layer during the process. Layer composition were changed using Cu rich or Fe rich ingredients. Magnetic properties of the particles strongly depend on the composition of covered material, indicating for their core-shell structure.

19

Magnetic resonance study of γ-Fe2O3 nanoparticles dressed in oxygen based free radicals

Guskos N., Typek J., Zolnierkiewicz G., Wardal K., Guskos A., Berczynski P., Petridis D.

Materials Science Poland

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2013

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Vol. 31, No. 4

587--594

EN

Two composites consisting of g-Fe2O3 (maghemite) nanoparticles covered by two different oxygen-based free radicals derived from a 4-(methylamino)phenol sulphate and 8-hydroxy-1,3,6-trisulfonic trisodium salt acid were prepared and investigated by the magnetic resonance method in the 4 – 300 K range. Both composites displayed broad and very intense ferromagnetic resonance (FMR) lines originating from g-Fe2O3 agglomerated nanoparticles. The FMR spectrum was fitted satisfactorily at each temperature by two Landau-Lifshitz functions reflecting the existence of magnetic anisotropy in the investigated system. The temperature dependence of the obtained FMR parameters (resonance field, linewidth, integrated intensity) was studied and the results were interpreted in terms of magnetic interactions between free radicals and nanoparticle agglomerates. A comparison with previously studied similar systems containing maghemite nanoparticles was made and conclusions about the role of free radicals were drawn.

20

Ferromagnetyczne nanoproszki metali

Łuszczyk K

Laboratorium - Przegląd Ogólnopolski

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2013

|

nr 7-8

50--53

PL

Przedmiotem niniejszego artykułu jest zaprezentowanie przykładowych ferromagnetycznych proszków na bazie nano- oraz submikrocząsek kobaltu i żelaza. Zainteresowanie samymi nanostrukturami magnetycznymi związane jest głównie z ich unikalnymi właściwościami oraz dużym potencjałem aplikacyjnym. Materiały metaliczne w formie proszkowej uzyskano metodą redukcji chemicznej. Submikrocząstki żelaza w celu zapobiegania niepożądanemu procesowi agregacji były dodatkowo stabilizowane przez przyłączenie ich do powierzchni modyfikowanych grupami aminowymi nośników krzemionkowych otrzymywanych metodą zol-żel.

EN

The subject of this article is the presentation of exemplary ferromagnetic powders based on cobalt and iron nano- or submicroparticles. Research interest in magnetic nanostructures is mainly related to their unique properties and huge potential for applications. The selected metal powders were obtained by chemical reduction. Additionally, iron submicroparticles were deposited on the surface of amine-modified silica spheres obtained by the sol-gel method. Silica matrix was aimed to prevent metal particles from negative process of aggregation into larger clusters.