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Вид документа : Однотомное издание
Шифр издания :
Автор(ы) : Arkhipkin V. G., Myslivets S. A.
Заглавие : Ultranarrow resonance peaks in the transmission and reflection spectra of a photonic crystal cavity with Raman gain
Место публикации : ArXiv. - 2009. - Ст.0909.0092
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Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Kniazev I.
Заглавие : Magnetic transition study in e-Fe2O3 by conventional Mössbauer spectroscopy and synchrotron radiation source
Коллективы : EBS Workshop on Nuclear Resonance Scattering
Место публикации : NRS workshop: list of posters. - 2019. - Ст.9
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Dmitriev A. I., Kulikov A. V., Gilmutdinov I. F., Dremova N. N., Mazitov A. A., Dmitrieva M. S., Alekseev S. I., Myagkov V. G.
Заглавие : Magnetic Anisotropy in Thin Films of FePt Detected by the Ferromagnetic Resonance Method
Коллективы : [007-00160-18-00]
Место публикации : J. Surf. Ingestig. - 2019. - Vol. 13, Is. 2. - P.210-214. - ISSN 1027-4510, DOI 10.1134/S102745101902006X. - ISSN 1819-7094(eISSN)
Примечания : Cited References: 18. - The study was performed under state contract no. 007-00160-18-00. The dependences of the magnetic moment of the samples on the magnetic-field intensity were measured using instruments of the Federal center for shared facilities for the physical-chemical research of compounds and materials at Kazan Federal University.
Ключевые слова (''Своб.индексиров.''): fept thin films--ferromagnetic resonance--magnetic anisotropy
Аннотация: FePt thin films are made via the heat treatment of structures containing Pt (001) and Fe (001) epitaxial layers. X-ray spectral analysis and field-emission scanning electron microscopy show that the samples contain the cubic L12–Fe3Pt phase and the tetragonal L10–FePt phase. The magnetic anisotropy of the thin films is studied by ferromagnetic resonance and magnetometric methods. The contributions from the cubic and tetragonal phases to the ferromagnetic-resonance spectrum of the sample are distinguished. The key characteristics of thin films which determine their practical applicability are determined: the Gilbert damping parameter G ~ 0.4, the first and second crystal anisotropy constants K1⊥ = –4.08 × 106 erg/cm3, K2⊥ = 1.34 × 106 erg/cm3, K2|| = –9.76 × 104 erg/cm3.
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Вид документа : Статья из сборника (выпуск монографической серии)
Шифр издания :
Автор(ы) : Togushova Yu.N., Korshunov M. M.
Заглавие : Role of Interactions in the Energy of the Spin Resonance Peak in Fe-Based Superconductors
Коллективы : International Conference on Solid Compounds of Transition Elements
Место публикации : Solid State Phenomena. - 2019. - Vol. 289 SSP. - P.212-217. - , DOI 10.4028/www.scientific.net/SSP.289.212
Примечания : Cited References: 30. - This work was supported in part by the Russian Foundation for Basic Research (grant 16-02-00098), Presidium of RAS Program for the Fundamental Studies #12, and “BASIS” Foundation for Development of Theoretical Physics and Mathematics. MMK acknowledges support by the Gosbudget program # 0356-2017-0030.
Предметные рубрики: Solid Compounds of Transition Elements III
Аннотация: We consider the spin response within the five-orbital model for iron-based superconductors and study two cases: equal and unequal gaps in different bands. In the first case, the spin resonance peak in the superconducting state appears below the characteristic energy scale determined by the gap magnitude, 2ΔL. In the second case, the energy scale corresponds to the sum of smaller and larger gap magnitudes, ΔL+ΔS. Increasing the values of the Hubbard interaction and the Hund's exchange, we observe a shift of the spin resonance energy to lower frequencies.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Orlov V. A., Ivanov A. A., Orlova I. N.
Заглавие : On the Effect of Magnetostatic Interaction on the Collective Motion of Vortex Domain Walls in a Pair of Nanostripes
Место публикации : Phys. Status Solidi B. - 2019. - Vol. 256, Is. 10. - Ст.1900113. - ISSN 03701972 (ISSN) , DOI 10.1002/pssb.201900113
Примечания : Cited References: 49. - The reported study was funded by RFBR according to the research project no. 18-02-00161.
Аннотация: The periodic motion of interacting vortex domain walls in a pair of nanostripes has been analytically and numerically investigated. A model consisting of two parallel nanostripes with the domain magnetization structure has been proposed, where domains are separated by vortex walls. The magnetic subsystems of the stripes magnetostatically interact, which causes the existence of normal magnetic vortex motion modes in the latter. Frequencies of the collective magnetization modes have been calculated using empirical expressions for the magnetic energy of interaction between vortex walls. It is shown that not any combinations of the polarity and chirality lead to the resonance magnetization behavior in ac fields. © 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Vorotynov A. M., Rudenko V. V., Ovchinnikov S. G., Molokeev M. S.
Заглавие : Electron Paramagnetic Resonance of Cr3+ Ions in ABO(3) (A = Sc, In, Ga) Diamagnetic Crystals
Место публикации : J. Exp. Theor. Phys. - 2018. - Vol. 127, Is. 6. - P.1067-1073. - ISSN 1063-7761, DOI 10.1134/S1063776118120245. - ISSN 1090-6509(eISSN)
Примечания : Cited References: 14
Предметные рубрики: SPIN-RESONANCE
PAIRS
ANISOTROPY
VBO3
Аннотация: A magnetic resonance method is applied to the investigation of a number of isostructural diamagnetic compounds ABO3 (A = Sc, In, and Ga) with small additions of Cr3+ ions (S = 3/2) sufficient to observe single-ion and pair spectra. It is shown that the resonance spectra for isolated Cr3+ ions can be described to a good accuracy by the ordinary axial spin Hamiltonian for 3d ions in octahedral oxygen environment. The parameters of the spin Hamiltonian are determined for single Cr3+ ion and Cr3+–Cr3+ pair. Lattice distorsions of the parent ABO3 crystals caused by the Cr3+ impurities is discussed.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Belyaev B. A., Boev N. M., Izotov A. V., Solovev P. N.
Заглавие : Study of Peculiarities of the Microwave Absorption Spectrum of Nanocrystalline Thin Magnetic Films
Коллективы : Ministry of Education and Science of the Russian Federation [RFMEFI60417X0179]
Место публикации : Russ. Phys. J. - 2019. - Vol. 61, Is. 10. - P.1798-1805. - ISSN 1064-8887, DOI 10.1007/s11182-019-01603-4. - ISSN 1573-9228(eISSN)
Примечания : Cited References: 22. - This work was supported by the Ministry of Education and Science of the Russian Federation, project No. RFMEFI60417X0179.
Предметные рубрики: MICROMAGNETIC CALCULATION
SIMULATIONS
PARTICLES
MODES
Ключевые слова (''Своб.индексиров.''): micromagnetic modeling--nanocrystallites--random magnetic anisotropy--ferromagnetic resonance--microwave
Аннотация: Based on the micromagnetic model which takes into account the random distribution of the uniaxial magnetic anisotropy directions in crystallites of a nanocrystalline film, an effective method has been implemented for calculation of the magnetization dynamics in microwave fields. For a certain range of crystallite sizes, when the energy of the random magnetic anisotropy is comparable to the exchange energy, a significant change of the ferromagnetic resonance field, broadening of the resonance line, and the appearance of an asymmetry in the shape of the resonance curve were found. With an increase of the crystallite sizes, the resonance field first grows, then, it quickly decreases to its minimum, and then, it grows again to reach saturation. In this case, the steepness of the left slope of the broadening resonance curve first decreases faster than that of the right slope, leading to the symmetry breaking of the resonance curve shape, then, the curve becomes symmetrical again, and then, the steepness of the left slope becomes greater than that of the right slope.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Izotov A. V., Belyaev B. A., Solovev P. N., Boev N. M.
Заглавие : Two-Magnon Relaxation Processes in Nanocrystalline Thin Magnetic Films
Коллективы : Russian Ministry of Education and Science [3.1031.2017/PCh]
Место публикации : Russ. Phys. J. - 2019. - Vol. 61, Is. 12. - P.2313-2320. - ISSN 1064-8887, DOI 10.1007/s11182-019-01673-4. - ISSN 1573-9228(eISSN)
Примечания : Cited References: 25. - This research was done with support of the Russian Ministry of Education and Science, task No. 3.1031.2017/PCh.
Предметные рубрики: FERROMAGNETIC-RESONANCE LINEWIDTH
MICROMAGNETIC CALCULATION
SCATTERING
Аннотация: Numerical analysis of the micromagnetic model was used to reveal the ‘resonance’ feature of relaxation processes in nanocrystalline thin magnetic films. This feature manifests itself in the form of sharp broadening of the ferromagnetic resonance (FMR) line at a certain frequency f1 depending on magnetic characteristics of the film, and is observed only in films the thickness of which exceeds some threshold value dmin. Sharp broadening of the FMR line is accompanied by significant shift of the resonance field, whereas the shift value changes the sign at frequency ~ f1. It was shown analytically that the nature of observed effects is associated with the two-magnon process of spin waves scattering on quasi-periodic magnetic microstructure – magnetization ‘ripple’. Obtained expressions for the threshold value of film thickness dmin and frequency of maximum broadening of FMR line f1 agree well with the results of numerical computation of micromagnetic model.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Morozov E. V., Buznik V. M., Bespalov A. S., Grashchenkov D. V.
Заглавие : Magnetic Resonance Imaging of Water Absorption by Highly Porous Ceramic Materials
Место публикации : Dokl. Chem. - 2019. - Vol. 484, Is. 2. - P.44-47. - ISSN 00125008 (ISSN), DOI 10.1134/S0012500819020058
Примечания : Cited References: 9. - The studies were performed using equipment of KRTsKP FITs "KNTs SO RAN" in the framework of the program of basic research of the Russian Academy of Sciences (project no. V.44.1.7.) regarding the development of the MRI methodology for studying composite and porous materials, and also supported by the Russian Foundation for Basic Research (project no. 16-29-05334ofi_m "Scientific foundations for creating thin-film coatings with controlled wettability") regarding the development of water-repellent porous materials.
Ключевые слова (''Своб.индексиров.''): magnetic resonance imaging--porosity--ceramic materials--hydrophobic coatings--adsorption--capillary phenomena
Аннотация: A nontrivial character of water absorption in highly porous ceramic materials has been demonstrated for the first time by magnetic resonance imaging: a phenomenon of hygroscopic memory has been detected consisting in the concentration of adsorbed water in certain areas inside the sample, repeated during subsequent wetting with water. It has been shown that hydrophobization of the material by applying fluoro paraffin coatings to oxide fibers using the method of dissolution of fluoropolymers in supercritical CO2 has a significant impact on the transport of water into products and can be considered an efficient means of protecting porous materials from moisture. The results demonstrate the capabilities of the MRI method in studying the water absorption and identifying water migration pathways in highly porous materials.
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10.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Vazhenina I. G., Chekanova L. A., Iskhakov R. S.
Заглавие : Spin-Wave Resonance Detection of Nanostructured Magnetic Alloy Inhomogeneities, Using the Example of Co–P and Co–Ni Planar Systems
Место публикации : Bull. Russ. Acad. Sci. Phys. - 2019. - Vol. 83, Is. 6. - P.713-715. - ISSN 10628738 (ISSN), DOI 10.3103/S1062873819060364
Примечания : Cited References: 12. - The reported study was funded by the Russian Foundation for Basic Research, the Government of Krasnoyarsk Krai, and the Krasnoyarsk Regional Fund of Science as part of research project no. 18-42-243005 “Synthesis and Investigation of Magnetic Properties of Gradient Materials Characterized by a Predetermined Type of the Magnetic Parameter Change.”
Аннотация: Inhomogeneous layered magnetic thin films of amorphous and nanocrystalline Со–Р and Co–Ni alloys are studied via spin-wave resonance. It is found that the formation of a magnetic potential profile specified over the coating thickness leads to characteristic modifications of the spin-wave resonance spectrum. Another important factor that determines the type of modification is the dominant magnetic parameter (the constant of magnetization or exchange coupling).
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11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Комогорцев, Сергей Викторович, Крайнова Г. С., Ильин Н. В., Плотников В. С., Чеканова, Лидия Александровна, Немцев, Иван Васильевич, Юркин, Глеб Юрьевич, Исхаков, Рауф Садыкович, Ятманов Д. А.
Заглавие : Особенности ферромагнитного резонанса лент аморфных сплавов FeSiBNbCu различного состава
Место публикации : Материаловедение. - 2019. - № 7. - С. 8-11. - ISSN 1684-579X, DOI 10.31044/1684-579X-2019-0-7-8-11
Примечания : Библиогр.: 25
Аннотация: Исследовано резонансное поглощение СВЧ-волн в аморфных лентах FeSiBNbCu различного состава, полученных быстрой закалкой из расплава. Для величины эффективной намагниченности, рассчитанной по величине резонансного поля, наблюдается линейное снижение с ростом концентрации примеси бора, меди, а также суммарного количества атомов немагнитной примеси в лентах сплава FeSiBNbCu на основе железа.The resonance absorption of microwaves in amorphous FeSiBNbCu tapes of different compositions, prepared by rapid quenching from a melt has been studied. A linear decrease in effective magnetization with increasing boron, copper, and a total nonmagnetic impurity concentration in the FeSiBNbCu iron-based alloy tapes was observed.
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12.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Belyaev B. A., Izotov A. V., Skomorokhov G. V., Solovev P. N.
Заглавие : Experimental study of the magnetic characteristics of nanocrystalline thin films: the role of edge effects
Коллективы : RFBRRussian Foundation for Basic Research (RFBR) [18-32-00086]; Ministry of Science and Higher Education of the Russian Federation [3.1031.2017/PCh]
Место публикации : Mater. Res. Express. - 2019. - Vol. 6, Is. 11. - Ст.116105. - ISSN 2053-1591, DOI 10.1088/2053-1591/ab4456
Примечания : Cited References: 37. - This work was supported by RFBR according to the research project no. 18-32-00086 and by the Ministry of Science and Higher Education of the Russian Federation no. 3.1031.2017/PCh.
Предметные рубрики: FERROMAGNETIC-RESONANCE
ANISOTROPIES
ROUGHNESS
SUBSTRATE
Аннотация: Magnetic characteristics and their spatial distribution of magnetron sputtered nanocrystalline NiFe thin films of various compositions were investigated by ferromagnetic resonance (FMR) and magneto-optical Kerr effect microscopy. A sharp increase in the FMR line width and a strong deviation of the uniaxial magnetic anisotropy field were observed near the film edges. It was shown that the observed magnetic anisotropy behavior can be explained by assuming that besides the field-induced uniaxial magnetic anisotropy an additional source of the uniaxial anisotropy near the film edges exists, with the easy axis parallel to the edges. The possible origins of this additional contribution were discussed.
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13.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Korshunov M. M., Shestakov V. A., Togushova Yu. N.
Заглавие : Magnetic interactions, superconductivity, and spin-resonance peak in iron-based materials
Коллективы : Российская академия наук, Уральское отделение РАН, Институт физики металлов им. М. Н. Михеева Уральского отделения РАН, Уральский федеральный университет им. первого Президента России Б.Н. Ельцина, Российский фонд фундаментальных исследований, Euro-Asian Symposium "Trends in MAGnetism", "Trends in MAGnetism", Euro-Asian Symposium
Место публикации : Euro-asian symposium "Trends in magnetism" (EASTMAG-2019): Book of abstracts/ чл. конс. ком.: S. G. Ovchinnikov, N. V. Volkov [et al.]; чл. прогр. ком. D. M. Dzebisashvili [et al.]. - 2019. - Vol. 2. - Ст.I.I1. - P.108. - ISBN 978-5-9500855-7-4 (Шифр В33/E12-125657784)
Примечания : Cited References: 14. - Support by Presidium of RAS Program for the Fundamental Studies #12 “BASIS” Foundation for Development of Theoretical Physics and Mathematics is acknowledged
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14.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Pankrats A. I., Kolkov M. I., Balaev A. D., Shabanov A. V., Vasiliev A. D.
Заглавие : Forming a ferrimagnetic-like structure in the PbMn1−xFexBO4 (x ≈ 0.1) single crystal upon partial substitution
Место публикации : J. Magn. Magn. Mater. - 2020. - Vol. 497. - Ст.165997. - ISSN 03048853 (ISSN), DOI 10.1016/j.jmmm.2019.165997
Примечания : Cited References: 25. - The authors are grateful to S. Nikitin for help in the specific heat measurements in a magnetic field and S. Martynov for fruitful discussions. This study was funded by RFBR and the Government of Krasnoyarsk Territory , Krasnoyarsk Regional Fund of Science , to the research project no. 18-42-240008 “Effect of Magnetic Structure on the Magnetodielectric Properties of Oxide Crystals Containing Stereoactive Ions Pb 2+ and Bi 3+”.
Аннотация: The PbMn1−xFexBO4 (x ≈ 0.1) orthoborate single crystals have been grown for the first time by spontaneous crystallization and their magnetic and resonance properties and specific heat have been examined. It has been established that partial substitution of iron ions for manganese ones leads to an increase in the Curie temperature to 34.2 K from its value of 30.3 K in the unsubstituted crystal, enhances the magnetic anisotropy, and reduces the saturation magnetization. The magnetization drop is explained in the framework of the model of a ferrimagnetic-like structure, in which the magnetic moments of iron and manganese ions form ferromagnetic subsystems coupled by the antiferromagnetic exchange. It has been found that under magnetization along the rhombic b axis the magnetic moments switch stepwise to the magnetic field direction in a certain critical field. The spin-reorientation transition is the first-order one. This feature of the crystal magnetization does not allow the experimental ferromagnetic resonance frequency-field dependence for the rhombic b axis to be described using the calculation for a simple rhombic ferromagnet. It has been established that the increase in the magnetic anisotropy of the crystal upon substitution leads to an increase in the energy gap in the ferromagnetic resonance spectrum to 121.5 GHz at T = 4.2 K.
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15.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Eremina R. M., Moshkina E. M., Gavrilova T. P., Muftakhutdinov A. R., Gilmutdinov I. F.
Заглавие : Investigation of the Magnetic Properties of Warwickite Mn0.89Mg1.11BO4
Место публикации : Bull. Russ. Acad. Sci. Phys. - 2019. - Vol. 83, Is. 7. - P.792-794. - ISSN 10628738 (ISSN), DOI 10.3103/S106287381907013X
Примечания : Cited References: 3. - This work was supported by the Russian Foundation for Basic Research; the Administration of Krasnoyarsk Krai; and the Krasnoyarsk Krai Science Foundation, project no. 18-42-243007.
Аннотация: The temperature dependences of the magnetic susceptibility in magnetic fields applied parallel and perpendicular to axis с of a Mn0.89Mg1.11BO4 single crystal were measured. Spin ordering typical of an antiferromagnetic with an easy magnetization axis was observed below 16 K. The Dzyaloshinskii–Moriya interaction between spins of manganese ions in Mn0.89Mg1.11BO4 was estimated by analyzing the EPR linewidth. © 2019, Allerton Press, Inc.
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16.

Вид документа : Статья из сборника (однотомник)
Шифр издания :
Автор(ы) : Korshunov M. M., Shestakov V. A., Togushova Yu. N.
Заглавие : Spin resonance peak in the superconducting state of iron-based material
Коллективы : Superstripes, International conference
Место публикации : Superstripes 2019 - Quantum Complex Matter: Book of abstracts of the int. conf. - 2019. - P.50-51. - ISBN 978-88-6683-099-3
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17.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Бедарев В. А., Меренков Д. Н., Кобец М. И., Звягин А. А., Попережай С. Н., Гнатченко С. Л., Zajarniuk T., Vasevych T., Gutowska M. U., Szewczyk A., Гудим, Ирина Анатольевна
Заглавие : Проявление спиновых корреляций в монокристалле ErAl3(BO3)4
Место публикации : Физ. низких температур. - 2019. - Т. 45, № 9. - С. 1217-1222. - ISSN 0132-6414. - ISSN 1816-0328 (eISSN)
Примечания : Библиогр.: 15
Аннотация: Установлено наличие существенного магнитного вклада в удельную теплоемкость монокристалла ErAl3(BO3)4 при температурах менее 5 К. Результаты измерений спектров ЭПР при 4,2 К также свидетельствуют о проявлении ближнего магнитного порядка. Полученные данные обсуждаются в рамках модели, учитывающей спин-спиновое взаимодействие между редкоземельными ионами в парных кластерах.Встановлено присутність суттєвого магнітного внеску в питому теплоємність монокристалу ErAl3(BO3)4 при температурах нижче 5 К. Результати вимірювань спектрів ЕПР при температурі 4,2 К також свідчать про прояв близького магнітного порядку. Отримані дані обговорюються у рамках моделі, яка враховує спін-спінову взаємодію між рідкісноземельними іонами у парних кластерах.
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18.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Morozov E. V., Yushmanov, Pavel, V, Martyanov, Oleg N.
Заглавие : Temperature-Triggered Rearrangement of Asphaltene Aggregates as Revealed by Pulsed-Field Gradient NMR
Коллективы : Russian Science FoundationRussian Science Foundation (RSF) [15-19-00119]
Место публикации : Energy Fuels. - 2019. - Vol. 33, Is. 8. - P.6934-6945. - ISSN 0887-0624, DOI 10.1021/acs.energyfuels.9b00600. - ISSN 1520-5029(eISSN)
Примечания : Cited References: 119. - This research was performed using the equipment of Krasnoyarsk Regional Research Equipment Centre of Siberian Branch of Russian Academy of Sciences with the financial support of Russian Science Foundation (Project No. 15-19-00119).
Предметные рубрики: CRITICAL NANOAGGREGATE CONCENTRATION
ELECTRON-SPIN-RESONANCE
Аннотация: The tendency of asphaltenes for aggregation followed by precipitation and deposition plays a crucial role in the petroleum industry since these processes present severe problems during the production, recovery, and processing of crude oils and fossil hydrocarbon feedstocks. The dynamics of oil asphaltene aggregates dissolved in chloroform at different concentrations varied in a wide range that was investigated at temperatures from 0 to 55 °C using the Pulsed-Field Gradient NMR technique. The components attributed to nanoaggregates and macroaggregates were successfully resolved, which allowed us to measure their diffusion coefficients. The diffusion coefficients for all types of aggregates grow as the asphaltene concentration decreases, whereas the partial weight of the aggregates increases with the increase of asphaltene concentration. The difference in diffusion behavior of the aggregates of different types was registered when passing the critical concentration range 10–20 g/L. The nano- and macroaggregates behave independently when the asphaltene concentration is higher than 20 g/L (concentrated regime), while below 20 g/L (semidiluted regime) the components related to the different types of aggregates cannot be properly resolved. It was found that regardless of the asphaltene concentration, the diffusion coefficients for nano- and macroaggregates demonstrate similar temperature behavior giving the straight lines in the Arrhenius coordinates which change their slopes when passing the temperature range 20–30 °C. The phenomenon evidences the thermally induced cleavage of noncovalent bonds with subsequent rearrangement of asphaltene aggregates that is observed for all concentration regimes covering the existence of asphaltene aggregates of all types. The data obtained are well consistent with the modern concept of asphaltene aggregate structure and fairly agree with the data obtained earlier. We believe these results will contribute essentially to a better understanding of the fundamental behavior of asphaltenes and their aggregates, providing a deep insight into aggregate transformation triggered by the temperature.
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19.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Korshunov M. M., Togushova Yu.N.
Заглавие : Effect of the spin-orbit coupling and impurity scattering on the spin resonance peak in three-orbital model for Fe-based superconductors
Место публикации : J. Sib. Fed. Univ. Math. Phys. - 2018. - Vol. 11, Is. 1. - P.108-116. - ISSN 19971397 (ISSN), DOI 10.17516/1997-1397-2018-11-1-108-116; Журн. СФУ. Сер. "Математика и физика"
Примечания : Cited References: 27
Аннотация: Here we study a combined effect of the spin-orbit coupling and scattering on the nonmagnetic disorder on the formation of the spin resonance peak in iron-based superconductors. Spin susceptibility is calculated within the random phase approximation. The spin resonance peak becomes broader with the increase of disorder and its frequency also shifts. At the same time, the spin response in the s state is different from that of the s++ state.Исследуется совместное влияние спин-орбитального взаимодействия и рассеяния на немагнитном беспорядке на формирование спин-резонансного пика в сверхпроводниках на основе железа. Спиновая восприимчивость вычислена в приближении хаотических фаз. Спин-резонансный пик становится шире с увеличением беспорядка, и его частота также смещается. В то же время спиновый отклик в состоянии s± отличается от такового в состоянии s++.
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20.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Lundin A. A., Zobov V. E.
Заглавие : Asymptotic similarity of time correlation functions and shape of the 13C and 29Si NMR spectra in diamond and silicon
Коллективы : Institute of Chemical Physics of the Russian Academy of Science [0082-2018-0005, TSITIS AAAA-A18-118020690203]
Место публикации : J. Exp. Theor. Phys. - 2018. - Vol. 127, Is. 2. - P.305-315. - ISSN 1063-7761, DOI 10.1134/S1063776118080216. - ISSN 1090-6509(eISSN)
Примечания : Cited References: 47. - We thank V.A. Atsarkin, V.V. Demidov, F.S. Dzheparov, and E. B. Feldman for the discussion of our results. This work was supported by a subsidy allocated by the Institute of Chemical Physics of the Russian Academy of Science for the State assignment, theme 0082-2018-0005, code TSITIS AAAA-A18-118020690203.
Предметные рубрики: SPIN SYSTEMS
LINE-SHAPES
RELAXATION
SOLIDS
PARAMAGNETS
RESONANCE
Аннотация: Based on the proposed theory, we have investigated the shape of the NMR absorption spectra for 13C and 29Si nuclei in diamond and silicon crystals attributable to the internuclear dipole–dipole interaction. In accordance with the available experimental data, we have considered both crystals with a 100% content of magnetoactive isotopes and crystals with a comparatively low dilution by nonmagnetic nuclei. The time correlation functions (the first of which is the Fourier transform of the NMR spectrum) arising in an infinite chain of coupled differential equations are shown to be mutually similar with a slight time delay. The proposed theory allows the spectrum to be calculated analytically. The results obtained agree satisfactorily with the experimental ones. It is noted that the mutual similarity of the time correlation functions is probably a corollary of the development of dynamical chaos in the system.
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