Главная
Авторизация
Фамилия
Пароль
 

Базы данных


Труды сотрудников ИФ СО РАН - результаты поиска

Вид поиска

Область поиска
в найденном
Формат представления найденных документов:
полный информационныйкраткий
Отсортировать найденные документы по:
авторузаглавиюгоду изданиятипу документа
Поисковый запрос: (<.>K=Superparamagnetic<.>)
Общее количество найденных документов : 33
Показаны документы с 1 по 20
1.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kolovskaya O. S., Zamay T. N., Zamay G. S., Babkin V. A., Medvedeva E. N., Neverova N. A., Kirichenko A. K., Zamay S. S., Lapin I. N., Morozov E. V., Sokolov A. Е., Narodov A. A., Fedorov D. G., Tomilin F. N., Zabluda V. N., Alekhina Yu., Lukyanenko K. A., Glazyrin Yu. E., Svetlichnyi V. A., Berezovski M. V., Kichkailo A. S.
Заглавие : Aptamer-conjugated superparamagnetic ferroarabinogalactan nanoparticles for targeted magnetodynamic therapy of cancer
Место публикации : Cancers. - 2020. - Vol. 12, Is. 1. - Ст.216. - ISSN 2072-6694 (eISSN), DOI 10.3390/cancers12010216
Примечания : Cited References: 46. - This research was funded by the Ministry of Science and Higher Education of the Russian Federation; project 0287-2019-0007
Аннотация: Nanotechnologies involving physical methods of tumor destruction using functional oligonucleotides are promising for targeted cancer therapy. Our study presents magnetodynamic therapy for selective elimination of tumor cells in vivo using DNA aptamer-functionalized magnetic nanoparticles exposed to a low frequency alternating magnetic field. We developed an enhanced targeting approach of cancer cells with aptamers and arabinogalactan. Aptamers to fibronectin (AS-14) and heat shock cognate 71 kDa protein (AS-42) facilitated the delivery of the nanoparticles to Ehrlich carcinoma cells, and arabinogalactan (AG) promoted internalization through asialoglycoprotein receptors. Specific delivery of the aptamer-modified FeAG nanoparticles to the tumor site was confirmed by magnetic resonance imaging (MRI). After the following treatment with a low frequency alternating magnetic field, AS-FeAG caused cancer cell death in vitro and tumor reduction in vivo. Histological analyses showed mechanical disruption of tumor tissues, total necrosis, cell lysis, and disruption of the extracellular matrix. The enhanced targeted magnetic theranostics with the aptamer conjugated superparamagnetic ferroarabinogalactans opens up a new venue for making biocompatible contrasting agents for MRI imaging and performing non-invasive anti-cancer therapies with a deep penetrated magnetic field.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
2.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kirillov V. L., Yakushkin S. S., Balaev D. A., Dubrovskiy A. A., Semenov S. V., Knyazev Yu. V., Bayukov O. A., Velikanov D. A., Yatsenko D. A., Martyanov O. N.
Заглавие : Dimethylsulfoxide as a media for one-stage synthesis of the Fe3O4-based ferrofluids with a controllable size distribution
Место публикации : Mater. Chem. Phys. - 2019. - Vol. 225. - P.292-297. - ISSN 02540584 (ISSN) , DOI 10.1016/j.matchemphys.2019.01.003
Примечания : Cited References: 36. - This work was supported by the Russian Science Foundation , project no. 17-12-01111.
Ключевые слова (''Своб.индексиров.''): ferrofluid--magnetite nanoparticles--one-step synthesis--superparamagnetic nanoparticles--ferromagnetic resonance
Аннотация: The ultrafine (d = 4 nm) magnetite ferrofluid with a narrow nanoparticle size distribution has been synthesized in one stage at room temperature from a solution of iron(II) and (III) chlorides in dimethylsulfoxide (DMSO) with the propylene epoxide admixture. This is the first example of obtaining a stable concentrated ultrafine magnetite/DMSO ferrofluid at room temperature. X-ray diffraction, transmission electron microscopy, ferromagnetic resonance, Mossbauer spectroscopy, and magnetostatic study have been used to elucidate the role of DMSO and the H2O/DMSO ratio in the formation of a stable colloid with a desired nanoparticle size. The initial stages of the magnetite nanoparticles formation have been investigated by the ferromagnetic resonance technique.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
3.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Balaev D. A., Stolyar S. V., Krasikov A. A., Bayukov O. A., Yaroslavtsev R. N., Velikanov D. A., Iskhakov R. S., Knyazev Yu. V.
Заглавие : Effect of the interparticle interactions on superparamagnetic relaxation
Коллективы : Российская академия наук, Физико-технический институт им. Е.К. Завойского ФИЦ Казанского научного центра РАН, Казанский (Приволжский) федеральный университет, Euro-Asian Symposium "Trends in MAGnetism", "Trends in MAGnetism", Euro-Asian Symposium
Место публикации : VIII Euro-Asian symposium "Trends in magnetism" (EASTMAG-2022): Book of abstracts/ program com. S. G. Ovchinnikov [et al.]. - 2022. - Vol. 1, Sect.: Magnetotransport, magnetooptics and magnetophotonics. - Ст.D.O11. - P.437-438. - ISBN 978-5-94469-051-7
Примечания : Cited References: 3. - This study was supported by the Russian Science Foundation, Project No. 21-72-00025 (https://rscf.ru/project/21-72-00025/)
Материалы симпозиума, ,
Найти похожие
4.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Balaev D. A., Krasikov A. A., Dubrovskiy A. A., Popkov S. I., Stolyar S. V., Iskhakov R. S., Ladygina V. P., Yaroslavtsev R. N.
Заглавие : Exchange bias in nano-ferrihydrite
Место публикации : J. Appl. Phys.: American Institute of Physics, 2016. - Vol. 120, Is. 18. - Ст.183903. - ISSN 00218979, DOI 10.1063/1.4967912
Примечания : Cited References: 43. - The authors are grateful to M. Volochaev for measurements and O. A. Bayukov for Mössbauer study.This work was supported in part by the Ministry of Education and Science of the Russian Federation.
Ключевые слова (''Своб.индексиров.''): anisotropy--cooling systems--hysteresis--magnetic fields--magnetic materials--magnetism--nanomagnetics--nanoparticles--particle size--characteristic value--exchange bias--exchange bias effects--external magnetic field--field cooling--high anisotropy--minor hysteresis loop--superparamagnetic blocking--hysteresis loops
Аннотация: We report the results of investigations of the effect of cooling in an external magnetic field starting from the temperature over superparamagnetic blocking temperature TB on the shift of magnetic hysteresis loops in systems of ferrihydrite nanoparticles from ∼2.5 to ∼5 nm in size with different TB values. In virtue of high anisotropy fields of ferrihydrite nanoparticles and open hysteresis loops in the range of experimentally attainable magnetic fields, the shape of hysteresis loops of such objects in the field-cooling mode is influenced by the minor hysteresis loop effect. A technique is proposed for distinguishing the exchange bias effect among the effects related to the minor hysteresis loops caused by high anisotropy fields of ferrihydrite particles. The exchange bias in ferrihydrite is stably observed for particles not less than 3 nm in size or with TB over 40 K, and its characteristic value increases with the particle size. © 2016 Author(s).
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
5.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : KRUSTALEV B. P., BALAEV A. D., SOSNIN V. M.
Заглавие : EXCHANGE INTERACTIONS IN SUPERPARAMAGNETIC NANOCLUSTER FILMS FE-SIO
Место публикации : Solid State Commun.: PERGAMON-ELSEVIER SCIENCE LTD, 1995. - Vol. 95, Is. 5. - P271-275. - ISSN 0038-1098, DOI 10.1016/0038-1098(95)00264-2
Примечания : Cited References: 9
Ключевые слова (''Своб.индексиров.''): nanostructures--thin films--exchange and superexchange
Аннотация: The magnetic properties of superparamagnetic films Fe-SiO have been investigated. It has been shown that a proper consideration of intra- and intercluster interactions describes well the magnetic behavior of the films. Their main parameters have been determined. On the basis of a proposed cluster model, the decrease of the effective magnetic moment per one iron atom is explained.
WOS
Найти похожие
6.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kliava J., Edelman I. S., Ivanova O. S., Ivantsov R. D., Bayukov O. A., Petrakovskaja E. A., Zaikovskiy V., Bruckental I., Yeshurun Y., Stepanov S.
Заглавие : Formation and evolution of magnetic nanoparticles in borate glass simultaneously doped with Fe and Mn oxides
Коллективы :
Место публикации : J. Appl. Phys.: AMER INST PHYSICS, 2008. - Vol. 104, Is. 10. - Ст.103917. - ISSN 0021-8979, DOI 10.1063/1.3021289
Примечания : Cited References: 37. - A financial support from the Russian Foundation for Basic Research (RFBR)-CNRS (Grant No. 07-02-92174) is highly appreciated. R. Ivantsov is grateful to the Russian Science Support Foundation. Y. Yeshurun acknowledges the support of the Israel Scienc Foundation (ISF).
Предметные рубрики: COBALT FERRITE PARTICLES
SUPERPARAMAGNETIC RESONANCE
GAMMA-FE2O3 NANOPARTICLES
MATRIX
SIZE
SYSTEMS
Ключевые слова (''Своб.индексиров.''): aluminium compounds--borate glasses--coercive force--faraday effect--heat treatment--iron compounds--magnetic hysteresis--magnetic particles--magnetic susceptibility--manganese compounds--mossbauer effect--nanoparticles--paramagnetic materials--potassium compounds--remanence--superparamagnetism--transmission electron microscopy--x-ray chemical analysis--atomic spectroscopy--auger electron spectroscopy--crystal structure--electric relays--electronic medical equipment--ferrite--ferrites--glass--heat treatment--hysteresis--hysteresis loops--magnetic properties--magnetic resonance measurement--magnetic susceptibility--magnetism--manganese--manganese compounds--molybdenum--nanoparticles--optical properties--ozone water treatment--polydispersity--superparamagnetism--borate glasses--concentration ratios--electron magnetic resonances--emr spectrums--experimental techniques--faraday rotations--glass compositions--glass matrixes--glass preparations--magnetic measurements--magnetic nano particles--magnetic orders--magnetically ordered systems--magneto-optical properties--manganese ferrites--mean diameters--mn oxides--phase states--polydisperse nanoparticles--remnant magnetizations--ssbauer spectroscopies--superparamagnetic--superparamagnetic states--thermal treatments--variable temperatures--magnetic materials
Аннотация: Evolution of the phase state of paramagnetic additions at various stages of synthesis and subsequent thermal treatment of glasses of the system Al(2)O(3)-K(2)O-B(2)O(3) simultaneously doped with Fe(2)O(3) and MnO is studied by means of a combination of experimental techniques: Faraday rotation (FR), electron magnetic resonance (EMR), transmission electron microscopy (TEM), Mossbauer spectroscopy, and magnetic measurements. Both FR and EMR show that magnetically ordered clusters occur already at the first stage of the glass preparation. In particular, for the ratio of the Fe and Mn oxides in the charge close to 3:2, fine magnetic nanoparticles are formed with characteristics similar to those of manganese ferrite. By computer simulating the EMR spectra at variable temperatures, a superparamagnetic nature of these nanoparticles is confirmed and their mean diameter is estimated as approximately 3.2 nm. In the thermally treated glasses larger magnetic nanoparticles are formed, giving rise to FR spectra, characteristic of magnetically ordered systems, and the EMR spectra different from those in as-prepared glasses but also showing superparamagnetic narrowing. The Mossbauer spectroscopy corroborates the manganese ferrite structure of the nanoparticles and indicates their coexistence in the ferrimagnetic and superparamagnetic states. The TEM shows the presence of polydisperse nanoparticles on the background of the glass matrix, and electron diffraction of a selected region containing larger particles indicates a crystal structure close to that of MnFe(2)O(4). Energy-dispersive atomic x-ray spectra confirm that the major part of Fe and Mn introduced to the glass composition is gathered in the particles, with the concentration ratio close to 2:1, characteristic of bulk MnFe(2)O(4). Magnetic hysteresis loops of samples subjected to an additional thermal treatment demonstrate a strong increase in the coercive force, remnant magnetization, and high-field magnetic susceptibility with temperature decrease. The consistent results obtained using various techniques demonstrate that the formation of nanoparticles with characteristics close to those of MnFe(2)O(4) confers to these glasses magnetic and magneto-optical properties typical of substances possessing magnetic order.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие
7.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Edelman I. S., Ivanova O. S., Petrakovskaja E. A., Velikanov D. A., Tarasov I. A., Zubavichus Y. V., Trofimova N. N., Zaikovskii V. I.
Заглавие : Formation, characterization and magnetic properties of maghemite γ-Fe2O3 nanoparticles in borate glasses
Коллективы : Russian Foundation for Basic Research - Russia [14-02-01211-a]; President of Russia [NSh-2886.2014.2]; Russian Ministry of Science and Education [RFMEFI61914X0002]
Место публикации : J. Alloys Compd.: Elsevier Science, 2015. - Vol. 624. - P.60-67. - ISSN 0925-8388, DOI 10.1016/j.jallcom.2014.11.059
Примечания : Cited References: 25. - This work was supported partly by the Russian Foundation for Basic Research - Russia, Grant No. 14-02-01211-a and by the President of Russia Grant No. NSh-2886.2014.2. This work was performed using the equipment of Unique Scientific Facility "Kurchatov Synchrotron Radiation Source'' supported by the Russian Ministry of Science and Education (project code RFMEFI61914X0002).
Предметные рубрики: SUPERPARAMAGNETIC RESONANCE
HYSTERESIS LOOPS
EXCHANGE BIAS
IONS
MATRIX
Ключевые слова (''Своб.индексиров.''): nanostructures--crystal structure and symmetry--magnetic measurements
Аннотация: A new type of nanocomposite materials based on maghemite, γ-Fe2O3, nanoparticles dispersed in borate glasses co-doped with low contents of iron together with the larger radius element combinations: Y and Bi, or Sm and Pb, or Y and Pb is studied. Nanoparticles arise as a result of heat treatment of the glasses which gives them properties characteristic of magnetically ordered substances. Transmission electron microscopy and XRD show that only one magnetic phase, namely γ-Fe2O3 nanoparticles, occurs in glasses subjected to the thermal treatment at 540 °C during 24 h independently on the doping element nature. At the same time doping element and their concentrations ratio in every combination affect the particles average size and glass magnetic properties, such as magnetization temperature dependences, Faraday rotation value and electron magnetic resonance spectrum characteristics.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
8.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Stolyar S. V., Li O. A., Nikolaeva E. D., Vorotynov A. M., Velikanov D. A., Iskhakov R. S., Pyankov V. F., Boev N. M., Kryukova O. V.
Заглавие : Frequency-field dependences of FMR in NiFe2O4 superparamagnetic powders
Коллективы : International Baltic Conference on Magnetism, Балтийский федеральный университет им. И. Канта
Место публикации : V International Baltic Conference on Magnetism. IBCM: Book of abstracts. - 2023. - P.138
Примечания : Cited References: 4
Материалы конференции,
Читать в сети ИФ
Найти похожие
9.

Вид документа : Однотомное издание
Шифр издания :
Автор(ы) : Iskhakov R. S., Frolov G. I., Zhigalov V. S., Prokof'ev D. E., Burkova L. V.
Заглавие : From superparamagnetic to magnetically ordered state in Co-Sm-О nanocrystalline films
Место публикации : Physics of Metals and Metallogra phy. - 2006. - Vol. 102, Suppl. 1. - P.S61-S63. - DOI 10.1134/S0031918X06140158
Примечания : Библиогр.: 11
Аннотация: Transition of the system of Co nanoparticles from a superparamagnetic state into the region of cooperative magnetic ordering caused by effects of magnetic interaction between particles has been analyzed. The possibility of the preparation of materials with soft magnetic properties and higher electrical resistivity was shown.
Смотреть статью,
Читать в сети ИФ
Найти похожие
10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Stolyar S. V., Li O. A., Nikolaeva E. D., Boev N. M., Vorotynov A. M., Velikanov D. A., Iskhakov R. S., Pyankov V. F., Knyazev Yu. V., Bayukov O. A., Shokhrina A. O., Molokeev M. S., Vasiliev A. D.
Заглавие : Heating of magnetic powders in the ferromagnetic resonance mode at a frequency of 8.9 GHz
Колич.характеристики :8 с
Коллективы : Nanophysics and Nanoelectronics, International Symposium
Место публикации : Phys. Solid State. - 2023. - Vol. 65, Is. 6. - P.963-970. - ISSN 10637834 (ISSN), DOI 10.21883/PSS.2023.06.56109.21H. - ISSN 10906460 (eISSN)
Примечания : Cited References: 25
Аннотация: Nickel ferrite nanoparticles 4 nm in size were synthesized by chemical deposition. Subsequent annealing at T=700°C for 5 h led to an increase in the particle size to 63 nm. The Mossbauer spectra and the frequency-field dependences of ferromagnetic resonance have been measured. It has been shown that freshly prepared powders are superparamagnetic at room temperature. The kinetic dependences of the heating of nanoparticles in the ferromagnetic resonance mode at a frequency of 8.9 GHz were measured. It was found that the maximum rate of temperature increase in this mode for a ferromagnetic powder is an order of magnitude greater than for the superparamagnetic state (1.2 and 0.13 K/s, respectively). The latter is determined by the saturation magnetization of the studied powders.
Смотреть статью,
Читать в сети ИФ
Найти похожие
11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Krasikov A. A., Knyazev Yu. V., Balaev D. A., Velikanov D. A., Stolyar S. V., Mikhlin Yu. L., Yaroslavtsev R. N., Iskhakov R. S.
Заглавие : Interparticle magnetic interactions and magnetic field dependence of superparamagnetic blocking temperature in ferrihydrite nanoparticle powder systems
Место публикации : Phys. B: Condens. Matter. - 2023. - Vol. 660. - Ст.414901. - ISSN 09214526 (ISSN), DOI 10.1016/j.physb.2023.414901. - ISSN 18732135 (eISSN)
Примечания : Cited References: 66. - This study was supported by his work was supported by the Russian Science Foundation, project no. 22-72-00134
Аннотация: In this study, nanoparticles of initial synthetic ferrihydrite have been coated with arabinogalactan. The synthesized series of samples with different degrees of coverage of particles has been characterized by X-ray photoelectron spectroscopy, Mossbauer spectroscopy, transmission electron microscopy and magnetometry. The superparamagnetic blocking temperature decreases monotonically with an increase in the degree of coverage of ferrihydrite particles, which is unambiguously related to the different role of the interparticle magnetic interactions in the investigated powder systems. Analysis of the field dependence of the blocking temperature within the random anisotropy model has shown that an increase in the degree of coverage of ferrihydrite particles leads to a decrease in the size of a cluster in which the behaviors of the nanoparticle magnetic moments are correlated. The results obtained have shown the possibility of effective control of the strength of magnetic interparticle interactions in powder ferrihydrite systems by coating nanoparticles with arabinogalactan.
Смотреть статью,
WOS,
Читать в сети ИФ
Найти похожие
12.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Iskhakov R. S., Denisova E. A., Kuzovnikova L. A., Komogortsev S. V.
Заглавие : Investigation of ferromagnetic and superparamagnetic particles of ball milled cobalt-copper alloys
Коллективы : Moscow International Symposium on Magnetism, Московский государственный университет им. М.В. Ломоносова, Российский фонд фундаментальных исследований
Место публикации : Moscow Int. Symp. on Magnet. (MISM-2008): June 20-25, 2008, Moscow : book of abstract. - 2008. - Ст.25PO-13-29. - p.769
Примечания : This work was supported by the RFBR and KRSF, project no.07-03-96808 and National Science Fund (2008, PhD RAS)
Читать в сети ИФ
Найти похожие
13.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Balaev D. A., Krasikov A. A., Knyazev Yu. V., Yaroslavtsev R. N., Velikanov D. A., Mikhlin Yu. L., Volochaev M. N., Bayukov O. A., Ladygina V. P., Stolyar S. V., Iskhakov R. S.
Заглавие : Magnetic collective state formation upon tuning the interparticle interactions in ensembles of ultrafine ferrihydrite nanoparticles
Колич.характеристики :13 с
Место публикации : Nano-Struct. Nano-Objects. - 2024. - Vol. 37. - Ст.101089. - ISSN 2352507X (ISSN), DOI 10.1016/j.nanoso.2023.101089. - ISSN 23525088 (eISSN)
Примечания : Cited References: 93. - The authors thank M.N. Volochaev for the TEM investigations
Аннотация: The results of a study of the dynamic (alternating current magnetic susceptibility) and static magnetic properties, as well as 57Fe Mössbauer spectrometry and ferromagnetic resonance of two-line ferrihydrite nanoparticle systems with varying intensities of magnetic interparticle interactions are reported. The strength of the magnetic interparticle interactions has been tuned by coating (with various degrees of coating) the ferrihydrite particles (2–4 nm in size and an average size ∼2.7 nm) of the initial synthetic sample by arabinogalactan. Also, a biogenic ferrihydrite sample (an average particle size of 2-nm) with a natural organic coating was studied and it has the weakest magnetic interparticle interactions among of all the samples. Relaxation times of the particle’s magnetic moment were determined by the data of static and dynamic magnetic susceptibilities and from analysis of 57Fe Mössbauer spectrometry. Based on the temperature dependences of the relaxation times, it has been concluded that the predominantly collective processes of freezing of the particle magnetic moments occur under the action of the magnetic interparticle interactions. It is shown that an important role in these processes is played by a magnetic subsystem of the surface spins of the particles. The effect of the interplay between the surface spin and magnetic moment subsystems on the static magnetic properties (low-temperature magnetic hysteresis loops) and the parameters of the microwave absorption line under the magnetic resonance conditions is discussed.
Смотреть статью,
Scopus,
Читать в сети ИФ
Найти похожие
14.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Iskhakov R. S., Frolov G. I., Zhigalov V. S., Prokof'ev D. E.
Заглавие : Magnetic interaction between superparamagnetic particles in nanogranular cobalt films
Место публикации : Tech. Phys. Lett.: AMER INST PHYSICS, 2004. - Vol. 30, Is. 8. - P687-689. - ISSN 1063-7850, DOI 10.1134/1.1792314
Примечания : Cited References: 12
Предметные рубрики: SINGLE-DOMAIN PARTICLES
BEHAVIOR
Аннотация: A system of cobalt nanoparticles exhibits a transition from the superparamagnetic state into the state with cooperative magnetic ordering caused by the magnetic interaction between Co particles. It is shown that this transition can be used for obtaining nanogranular materials possessing soft magnetic properties at a large electric resistivity. (C) 2004 MAIK "Nauka/Interperiodica".
WOS,
Scopus,
Читать в сети ИФ
Найти похожие
15.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Krasikov A. A., Knyazev Yu. V., Balaev D. A., Stolyar S. V., Ladygina V. P., Balaev A. D., Iskhakov R. S.
Заглавие : Magnetic interparticle interactions and superparamagnetic blocking of powder systems of biogenic ferrihydrite nanoparticles
Колич.характеристики :11 с
Место публикации : J. Exp. Theor. Phys. - 2023. - Vol. 137, Is. 6. - P.903-913. - ISSN 10637761 (ISSN), DOI 10.1134/S1063776123120075. - ISSN 10906509 (eISSN)
Примечания : Cited References: 58. - This study was supported by the Russian Science Foundation, project no. 22-72-00134
Аннотация: The magnetic-field dependence of the superparamagnetic-blocking temperature TB of systems of antiferromagnetically ordered ferrihydrite nanoparticles has been investigated and analyzed. We studied two powder systems of nanoparticles: particles of “biogenic” ferrihydrite (with an average size of 2.7 nm), released as a result of vital functions of bacteria and coated with a thin organic shell, and particles of biogenic ferrihydrite subjected to low-temperature annealing, which cause an increase in the average particle size (to 3.8 nm) and burning out of the organic shell. The character of the temperature dependences of magnetization, measured after cooling in a weak field, as well as the shape of the obtained dependences TB(H), demonstrate peculiar features, indicating the influence of magnetic interparticle interactions. A detailed analysis of the dependences TB(H) within the random magnetic anisotropy model made it possible to estimate quantitatively the intensity of magnetic particle–particle interactions and determine the magnetic anisotropy constants of individual ferrihydrite particles.
Смотреть статью,
Scopus,
Читать в сети ИФ
Найти похожие
16.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Edelman I. S., Ivanova O. S., Ivantsov R. D., Velikanov D. A., Zabluda V. N., Zubavichus Y., Veligzhanin A. A., Zaikovskiy V. I., Stepanov S., Artemenko A., Curely J., Kliava J.
Заглавие : Magnetic nanoparticles formed in glasses co-doped with iron and larger radius elements
Место публикации : J. Appl. Phys.: American Institute of Physics, 2012. - Vol. 112, Is. 8. - Ст.84331. - P. - ISSN 0021-8979, DOI 10.1063/1.4759244
Примечания : Cited References: 65. - This work was partly supported by the Russian Foundation for Basic Research, Grant Nos. 07-02-92174 RFBR-CNRS and 11-02-00972, and President of Russia Federation Grant No NSh 1044.2012.2. A. Artemenko acknowledges financial support from the Marie Curie International Incoming Fellowship within the 7th European Community Framework Programme (EPREXINA, GA 255662). The synchrotron measurements were supported via the Russian federal Contract No. 16.552.11.7003. The authors thank K. P. Polyakova for the preparation of thin films.
Предметные рубрики: SUPERPARAMAGNETIC RESONANCE
FERROMAGNETIC-RESONANCE
TEMPERATURE-DEPENDENCE
FERRITE NANOPARTICLES
OXIDE NANOPARTICLES
FARADAY-ROTATION
CERAMICS
ANISOTROPY
PARTICLES
SPECTRA
Аннотация: A new type of nanoparticle-containing glasses based on borate glasses co-doped with low contents of iron and larger radius elements, Dy, Tb, Gd, Ho, Er, Y, and Bi, is studied. Heat treatment of these glasses results in formation of magnetic nanoparticles, radically changing their physical properties. Transmission electron microscopy and synchrotron radiation-based techniques: x-ray diffraction, extended x-ray absorption fine structure, x-ray absorption near-edge structure, and small-angle x-ray scattering, show a broad distribution of nanoparticle sizes with characteristics depending on the treatment regime; a crystalline structure of these nanoparticles is detected in heat treated samples. Magnetic circular dichroism (MCD) studies of samples subjected to heat treatment as well as of maghemite, magnetite, and iron garnet allow to unambiguously assign the nanoparticle structure to maghemite, independently of co-dopant nature and of heat treatment regime used. Different features observed in the MCD spectra are related to different electron transitions in Fe3+ ions gathered in the nanoparticles. The static magnetization in heat treated samples has non-linear dependence on the magnetizing field with hysteresis. Zero-field cooled magnetization curves show that at higher temperatures the nanoparticles occur in superparamagnetic state with blocking temperatures above 100 K. Below ca. 20 K, a considerable contribution to both zero field-cooled and field-cooled magnetizations occurs from diluted paramagnetic ions. Variable-temperature electron magnetic resonance (EMR) studies unambiguously show that in as-prepared glasses paramagnetic ions are in diluted state and confirm the formation of magnetic nanoparticles already at earlier stages of heat treatment. Computer simulations of the EMR spectra corroborate the broad distribution of nanoparticle sizes found by "direct" techniques as well as superparamagnetic nanoparticle behaviour demonstrated in the magnetization studies. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4759244]
Смотреть статью,
Scopus,
WoS,
Читать в сети ИФ
Найти похожие
17.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Edelman I. S., Ivanova O. S., Zubavichus Y., Trofimova N. N., Zaikovskiy V. I., Artemenko A., Curely J., Kliava J.
Заглавие : Magnetic nanoparticles in borate glasses: Identification and sizing
Коллективы : Russian Foundation for Basic Research, Russian Foundation for Basic Research, International Conference on Optimization of Electrical and Electronic Equipmen (22 May - 24 May 2014; Bran, Romania)
Место публикации : International Conference on Optimization of Electrical and Electronic Equipment (OPTIM 2014): IEEE Computer Society, 2014. - P.95-104. - ISBN 978-1-4799-5183-3, DOI 10.1109/OPTIM.2014.6850939
Примечания : Cited References: 60
Предметные рубрики: Engineering, Electrical and Electronic
Ключевые слова (''Своб.индексиров.''): superparamagnetic resonance--ferromagnetic-resonance--ferrite nanoparticles--oxide nanoparticles--faraday-rotation--ceramics--iron--crystallization--anisotropy--particles
Аннотация: Heat treatment of borate glasses co-doped with low contents of iron and larger radius elements: Dy, Tb, Gd, Ho, Er, Y and Bi results in formation of magnetic nanoparticles, radically changing their physical properties. Transmission electron microscopy and synchrotron radiation-based techniques: XRD, EXAFS, XANES and SAXS, show a broad distribution of nanoparticle sizes with characteristic depending on the treatment regime; a crystalline structure of these nanoparticles is detected in heat treated samples. Magnetic circular dichroism (MCD) studies of samples subjected to heat treatment as well as of maghemite, magnetite and iron garnet allow to unambiguously assigning the nanoparticle structure to maghemite. Different features observed in the MCD spectra are related to different electron transitions in Fe3+ ions gathered in the nanoparticles. Variable-temperature electron magnetic resonance (EMR) studies confirm the formation of magnetic nanoparticles and the identification of their nature. Computer simulations of the EMR spectra corroborate the broad distribution of nanoparticle sizes found by 'direct' techniques. © 2014 IEEE.
Материалы конференции,
Материалы конференции,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие
18.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Pankrats A. I., Vorotynov A. M., Tugarinov V. I., Zharkov S. M., Abramova G. M., Zeer G. M., Ramasamy, Karthik, Gupta, Arunava
Заглавие : Magnetic resonance in CuCr2S4 nanoclusters and nanocrystals
Коллективы : Moscow International Symposium on Magnetism
Место публикации : Solid State Phenom.: Selected, peer reviewed papers/ ed.: N. Perov, A. Semisalova: Trans Tech Publications Ltd, 2015. - Vol. 233-234: Achievements in Magnetism. - P.542-545. - ISSN 1662-9779, DOI 10.4028/www.scientific.net/SSP.233-234.542. - ISSN 978-3-03835-482-6
Примечания : Cited References: 6
Предметные рубрики: Achievements in magnetism
Ключевые слова (''Своб.индексиров.''): magnetic resonance--nanocrystal--superparamagnetic particles
Аннотация: Nanoclusters and nanocrystals of the room temperature magnetic spinel CuCr2S4 synthesized using a facile solution-based method were examined by magnetic resonance in a wide frequency range 9.6÷80 GHz and at temperatures down to 4.2 K. Decreasing of the resonance field and broadening of the resonance lines are found below ∼ 50 K for both the nanocluster and nanocube samples due to the freezing of magnetic moments of nanocubes and nanocrystalline particles constituting nanoclusters. Additional blocking temperature Tb≅300 K appears in nanoclusters due to the freezing of the magnetic moment of the entire cluster as a whole. Below this temperature, an additional low-field resonance line is found in the resonance spectra of nanoclusters at X-band.
Смотреть статью,
Материалы конференции,
Scopus,
Читать в сети ИФ
Найти похожие
19.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Yakushkin S. S., Balaev D. A., Shaikhutdinov K. A., Dubrovsky A. A., Bukhtiyarova G. A., Martyanov O. N.
Заглавие : Magnetic structure and size-effects in the system of epsilon-Fe2O3/SiO2 nanoparticles
Коллективы : Euro-Asian Symposium "Trends in MAGnetism", "Trends in MAGnetism", Euro-Asian Symposium, Институт физики им. Л.В. Киренского Сибирского отделения РАН
Место публикации : VI Euro-Asian Symposium "Trends in MAGnetism" (EASTMAG-2016): abstracts/ ed.: O. A. Maksimova, R. D. Ivantsov. - Krasnoyarsk: KIP RAS SB, 2016. - Ст.O9.5. - P.383. - ISBN 978-5-904603-06-9 (Шифр -478014040)
Примечания : References: 6
Ключевые слова (''Своб.индексиров.''): ε-fe2o3 nanoparticles--superparamagnetic nanoparticles--size effect--fmr
Найти похожие
20.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Edelman I., Kliava J.
Заглавие : Oxide glasses with magnetic nanoparticles: transparent magnets (Faraday rotation and electron magnetic resonance studies)
Коллективы : RFBR-CNRS [07-02-92174]
Разночтения заглавия :авие SCOPUS: Oxide glasses with magnetic nanoparticles: Transparent magnets (Faraday rotation and electron magnetic resonance studies)
Место публикации : Phys. Status Solidi B. - 2009. - Vol. 246, Is. 10. - P.2216-2231. - ISSN 0370-1972, DOI 10.1002/pssb.200945169
Примечания : Cited References: 87. - This work is supported in part by RFBR-CNRS joint project, grant No 07-02-92174. We are grateful to E. Petrakovskaja and O. Ivanova for measuring and discussing, respectively, the EMR spectra in thermally treated samples and the FR spectral and magnetic field dependences.
Предметные рубрики: SPIN-HAMILTONIAN PARAMETERS
SINGLE-DOMAIN PARTICLES
SUPERPARAMAGNETIC RESONANCE
CRYSTALLIZATION BEHAVIOR
FERRIMAGNETIC RESONANCE
PARAMAGNETIC-RESONANCE
TEMPERATURE-DEPENDENCE
COMPUTER-SIMULATIONS
FINE PARTICLES
BORATE GLASSES
Аннотация: In the first part of this paper we outline the state of the art in the field of magnetic nanoparticles in oxide glasses. We describe the theoretical background of two complementary techniques used for the studies of the state of paramagnetic ions, clusters and magnetic particles in a diamagnetic matrix, viz., magnetooptical Faraday rotation (FR) and electron magnetic resonance (EMIR) and we overview previous results obtained with these techniques for several glass systems. In the second part, we highlight the case of potassium-alumina-borate glasses - a glassy system where doping with paramagnetic oxides results in formation of magnetic particles at very low contents of paramagnetic additions: Fe(2)O(3) and MnO. In the special case when the ratio of the iron and manganese oxides in the charge is 3/2, magnetic nanoparticles with characteristics close to those of manganese ferrite are formed already at the first stage of the glass preparation. After thermal treatment all glasses show FR and EMR spectra attesting to the presence of superparamagnetic nanoparticles, characterized by relatively broad size and shape distributions. The formation of magnetic nanoparticles confers to these glasses magnetic and magnetooptical properties typical of magnetically ordered substances. At the same time, the glasses remain transparent in a part of the visible and near infrared spectral range and display a high FR value. Such properties make them particularly interesting for use as new media for various magneto-optical devices. (C) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
WOS,
Scopus,
Читать в сети ИФ
Найти похожие
 

Другие библиотеки

© Международная Ассоциация пользователей и разработчиков электронных библиотек и новых информационных технологий
(Ассоциация ЭБНИТ)