Библиотека института физики им. Л.В. Киренского СО РАН

Главная

Базы данных

Труды сотрудников ИФ СО РАН - результаты поиска

Вид поиска

Каталог книг и брошюр библиотеки ИФ СО РАН

Каталог журналов библиотеки ИФ СО РАН

Труды сотрудников ИФ СО РАН

Область поиска

в найденном

Формат представления найденных документов:
полный	информационный	краткий

Отсортировать найденные документы по:
автору	заглавию	году издания	типу документа

Поисковый запрос: (<.>S=Particles<.>)

Общее количество найденных документов : 30
Показаны документы с 1 по 20

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Lopatin V. N., Shepelevich N. V., Prostakova I. V.
Заглавие : Modelling optical properties of organic-mineral complexes in water ecosystems
Место публикации : J. Phys. D. - 2005. - Vol. 38, Is. 15. - P.2556-2563. - ISSN 0022-3727, DOI 10.1088/0022-3727/38/15/005
Примечания : Cited References: 22
Предметные рубрики: SCANNING FLOW-CYTOMETRY
LIGHT-SCATTERING
STRATIFIED SPHERE
PARTICLES
INDEX
Ключевые слова (''Своб.индексиров.''): approximation theory--ecosystems--inverse problems--light scattering--mathematical models--refractive index--suspensions (fluids)--water--generalization--integral light scattering indicatrix--organic-mineral complexes--spherical particles--complexation
Аннотация: Characteristics of organic-mineral complexes have been theoretically and experimentally studied in the paper, based on the method of integral light scattering indicatrix. Modelling of optical properties was realized using models of the coated spherical particles with a shell which is constant and changeable in the refractive index profile. General regularities have been revealed and generalized parameters for the method of integral light scattering indicatrix have been suggested.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Aver'yanov E. M.
Заглавие : Fluctuations of orientational order in a uniaxial nematic liquid crystal with biaxial molecules and its response to an external field
Место публикации : Phys. Solid State: AMER INST PHYSICS, 2003. - Vol. 45, Is. 5. - P990-1001. - ISSN 1063-7834, DOI 10.1134/1.1575350
Примечания : Cited References: 30
Предметные рубрики: PHASE-TRANSITION
SMECTIC-A
PARTICLES
SYSTEM
LANDAU
MODEL
Аннотация: Homogeneous thermal fluctuations of the orientational order parameters S and G of biaxial molecules in a uniaxial nematic liquid crystal are investigated in the framework of the molecular-statistical theory. It is demonstrated that the molecular biaxiality significantly affects the order parameters S and G, their temperature dependences in the nematic phase, the amplitude and the temperature dependence of the order parameter fluctuations in the nematic and isotropic phases, and the character of the transition from the nematic phase to the isotropic liquid phase. It is established that the fluctuations of the parameters S and G in the nematic phase are related to the temperature dependences of S and G and the susceptibilities chi(S) and chi(G) of the nematic liquid crystal to external fields, which leads to a change in the parameters S and G at a fixed director orientation. Explanations are offered for the known experimental data on the orientational ordering of biaxial molecules under the action of external fields in the isotropic phase of nematic liquid crystals. (C) 2003 MAIK "Nauka/Interperiodica".
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Edelman I. S., Ivantsov R., Vasiliev A., Stepanov S., Kornilova E., Zarubina T.
Заглавие : Superparamagnetic and ferrimagnetic nanoparticles in glass matrix
Место публикации : Physica B. - 2001. - Vol. 301, Is. 3-4. - P.203-211. - ISSN 0921-4526, DOI 10.1016/S0921-4526(01)00274-5
Примечания : Cited References: 9
Предметные рубрики: MAGNETIC-PROPERTIES
PARTICLES
FILMS
Ключевые слова (''Своб.индексиров.''): magnetic nanoparticles--faraday rotation--faraday rotation--magnetic nanoparticles--crystal structure--faraday effect--ferrimagnetic materials--glass--particle size analysis--superparamagnetism--x ray diffraction analysis--amorphous glass matrices--faraday rotations--nanostructured materials
Аннотация: Faraday rotation (FR) spectral, field, and temperature dependencies in oxide glasses with small additions of paramagnetic elements are investigated. Formation of ferrite nanoparticles in amorphous glass matrices is revealed by X-ray diffraction. Particles have crystal structure similar to spinel structure, their dimensions are about 10-24 nm. The FR field dependencies are typical for ferrimagnetic or superparamagnetic substances depending on particle size. Strong FR increase at the samples cooling (more than twice for some samples) in the temperature interval 105-273 K is observed. (C) 2001 Elsevier Science B.V. All rights reserved.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Frolov G. I., Bachina O. I., Zav'yalova M. M., Ravochkin S. I.
Заглавие : Magnetic properties of nanoparticles of 3d metals
Коллективы :
Место публикации : Tech. Phys.: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2008. - Vol. 53, Is. 8. - P1059-1064. - ISSN 1063-7842, DOI 10.1134/S1063784208080136
Примечания : Cited References: 19. - This study was supported by the targeted program "Development of the Research Potential of Higher Education Institutions," grant no. RNP.2.1.1.7376.
Предметные рубрики: CLUSTERS
IRON
PARTICLES
Аннотация: The influence of size effects on the coercive force, magnetization, and Curie temperature in nanoparticles of 3d metals is considered. It is shown that experimental results obtained during the last two decades provide new information on peculiar magnetic properties of these particles.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Li O. A., Lin C. -R., Chen H. -Y., Hsu, Hua-Shu, Shih K. -Y., Edelman I. S., Wu K. -W., Tseng Y. -T., Ovchinnikov S. G., Lee J. -S.
Заглавие : Size dependent magnetic and magneto-optical properties of Ni0.2Zn0.8Fe2O4 nanoparticles
Место публикации : J. Magn. Magn. Mater.: Elsevier, 2016. - Vol. 408. - P.206-212. - ISSN 03048853 (ISSN), DOI 10.1016/j.jmmm.2016.02.062
Примечания : Cited References: 51. - This work is supported by the Ministry of Science and Technology of Taiwan (MOST 103-2811-M-153 -001 and MOST 102-2112-M-153 -002 -MY3), and by the Russian Foundation for Basic Researches, grant No 14-02-01211.
Предметные рубрики: Zinc ferrite
Cation distribution
Sol-gel
Ni
ZnFe2O4
Spinel
Fe3O4
Particles
Spectra
State
Ключевые слова (''Своб.индексиров.''): nickel zinc ferrite--nanoparticles--magnetic properties--mcd
Аннотация: Ni0.2Zn0.8Fe2O4 spinel nanoparticles have been synthesized by combustion method. Average particles size varies from 15.5 to 50.0 nm depending on annealing temperature. Correlations between particles size and magnetic and magneto-optical properties are investigated. Magnetization dependences on temperature and external magnetic field correspond to the sum of paramagnetic and superparamagnetic response. Critical size of single-domain transition is found to be 15.9 nm. Magnetic circular dichroism (MCD) studies of nickel zinc spinel are presented here for the first time. The features in magnetic circular dichroism spectrum are assigned to the one-ion d-d transitions in Fe3+ and Ni2+ ions, as well to the intersublattice and intervalence charge transfer transitions. The MCD spectrum rearrangement was revealed with the change of the nanoparticles size. © 2016 Elsevier B.V. All rights reserved.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Balaev D. A., Krasikov A. A., Dubrovskiy A. A., Popkov S. I., Stolyar S. V., Bayukov O. A., Iskhakov R. S., Ladygina V. P., Yaroslavtsev R. N.
Заглавие : Magnetic properties of heat treated bacterial ferrihydrite nanoparticles
Место публикации : J. Magn. Magn. Mater.: Elsevier, 2016. - Vol. 410. - P.171-180. - ISSN 03048853 (ISSN), DOI 10.1016/j.jmmm.2016.02.059
Примечания : Cited References: 66. - TEM studies were performed on facility of Resource Sharing Center of Krasnoyarsk Scientific Center of Siberian Branch of Russian Academy of Sciences. Authors acknowledge to M.N. Volochaev for the TEM measurements.
Предметные рубрики: Hematite nanoparticles
NiO nanoparticles
Porous-glass
Ferritin
Particles
Temperature
Hysteresis
Transition
Anomalies
Mossbauer
Ключевые слова (''Своб.индексиров.''): ferrihydrite--nanoparticles--superparamagnetism
Аннотация: The magnetic properties of ferrihydrite nanoparticles, which are products of vital functions of Klebsiella oxitoca bacteria, have been studied. The initial powder containing the nanoparticles in an organic shell was subjected to low-temperature (T=160 °C) heat treatment for up to 240 h. The bacterial ferrihydrite particles exhibit a superparamagnetic behavior. Their characteristic blocking temperature increases from 26 to 80 K with the heat treatment. Analysis of the magnetization curves with regard to the magnetic moment distribution function and antiferromagnetic contribution shows that the low-temperature heat treatment enhances the average magnetic moment of a particle; i.e., the nanoparticles coarsen, probably due to their partial agglomeration during heat treatment. It was established that the blocking temperature nonlinearly depends on the particle volume. Therefore, a model was proposed that takes into account both the bulk and surface magnetic anisotropy. Using this model, the bulk and surface magnetic anisotropy constants KV≈1.7×105 erg/cm3 and KS≈0.055 erg/cm2 have been determined. The effect of the surface magnetic anisotropy of ferrihydrite nanoparticles on the observed magnetic hysteresis loops is discussed.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Vorotynov A. M., Petrakovskii G. A., Sablina K. A., Bovina A. F., Vasil'ev A. D.
Заглавие : EPR study of the Jahn-Teller effect of Cu2+ ions in ZnGa2O4
Место публикации : Phys. Solid State: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2010. - Vol. 52, Is. 11. - P2415-2418. - ISSN 1063-7834, DOI 10.1134/S1063783410110314
Примечания : Cited References: 12
Предметные рубрики: MAGNETIC-PROPERTIES
PARTICLES
CUFE2O4
Аннотация: The Jahn-Teller effect in the ZnGa2O4 spinel single crystal has been investigated using electron paramagnetic resonance of Cu2+ ions in the temperature range 110-560 K. It has been shown that copper ions occupy octahedral sites 16d in the ZnGa2O4 crystal with cubic symmetry O (h) (7) (Fd-3m). At T 560 K, the octahedra undergo tetragonal distortions (predominantly tension) and rotation around the fourfold axes by the angle theta a parts per thousand 2.6A degrees. The parameters of the spin Hamiltonian, which characterize the prolate (g (aEuro-)
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Edelman I. S., Morozova T. P., Zabluda V. M., Kim T. A., Turpanov I. A., Betenkova A. Ya., Dynnik Y. A.
Заглавие : Dispersion of Faraday rotation in Co/SiO2 multilayer films
Место публикации : JETP Letters. - 1996. - Vol. 63, Is. 4. - P.273-277. - ISSN 0021-3640, DOI 10.1134/1.567015
Примечания : Cited References: 9
Предметные рубрики: PARTICLES
Аннотация: The Faraday rotation spectra of Co/SiO2 multilayer films were found to be substantially different from the well-known spectra of homogeneous Co films. The character of these changes was studied as a function of the thicknesses of the ferromagnetic metal and the nonmagnetic dielectric layers. (C) 1996 American Institute of Physics.
WOS,
Scopus
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Knyazev Yu. V., Balaev D. A., Kirillov V. L., Bayukov O. A., Mart'yanov O. N.
Заглавие : Mossbauer spectroscopy study of the superparamagnetism of ultrasmall ε-Fe2O3 nanoparticles
Коллективы : Russian Science Foundation [17-12-01111]
Место публикации : JETP Letters. - 2018. - Vol. 108, Is. 8. - P.527-531. - ISSN 0021-3640, DOI 10.1134/S0021364018200092. - ISSN 1090-6487(eISSN)
Примечания : Cited References: 22. - This work was supported by the Russian Science Foundation (project no. 17-12-01111).
Предметные рубрики: High-temperature
Particles
ε-Fe2O3
Phase
Model
Аннотация: The superparamagnetism of an ensemble of ϵ-Fe2O3 nanoparticles with a mean size of 3.9 nm dispersed in a xerogel SiO2 matrix is studied by the Mössbauer spectroscopy method. It is shown that most nanoparticles at room temperature are in the superparamagnetic (unblocked) state. As the temperature decreases, the progressive blocking of the magnetic moments of the particles occurs, which is manifested in the Mössbauer spectra as the transformation of the quadrupole doublet into a Zeeman sextet. The analysis of the relative intensity of the superparamagnetic (quadrupole doublet) and magnetically split (sextets) spectral components in the range of 4–300 K provides the particle size distribution, which is in agreement with the transmission electron microscopy data. The values of the effective magnetic anisotropy constants (Keff) are determined, and the contribution of surface anisotropy (KS) is estimated for particles of various sizes. It is shown that the quantity Keff is inversely proportional to the particle size, which indicates the significant contribution of the surface to the magnetic state of the ϵ-Fe2O3 nanoparticles with the size of several nanometers.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

10.

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.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

11.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ikonnikov D. A., Myslivets S. A., Arkhipkin V. G., Vyunishev A. M.
Заглавие : 3D optical vortex lattices
Коллективы : Russian Science FoundationRussian Science Foundation (RSF) [19-12-00203]
Место публикации : Ann. Phys.-Berlin. - 2021. - Vol. 533, Is. 7. - Ст.2100114. - ISSN 0003-3804, DOI 10.1002/andp.202100114. - ISSN 1521-3889(eISSN)
Примечания : Cited References: 29. - This work was supported by the Russian Science Foundation (Grant No. 19-12-00203).The surface grating was fabricated and characterized at the Center for Collective Use of the Krasnoyarsk Scientific Center, Siberian Branch, Russian Academy of Sciences. The authors thank M. N. Volochaev and A. I. Zaitsev for help
Предметные рубрики: MANIPULATION
PARTICLES
ARRAY
BEAMS
GENERATION
TRANSPORT
VORTICES
Аннотация: Fresnel diffraction of light beams with a topological charge on a 2D regular amplitude transparency mask is studied. Numerical predictions show that the 3D optical lattices of optical vortices can be formed using the Talbot effect, with these predictions confirmed by the experimental reconstruction of all 3D optical vortex lattices. The periodicity of the 3D optical vortex lattices is determined by the light wavelength and periodicity of a transparency mask. Furthermore, it is shown that the optical vortices are created and annihilated during light propagation behind the mask with the preservation of the total topological charge. The 3D optical vortex lattices are considered to be tolerant to the perturbations induced by trapped particles caused by the features of the Talbot effect. The 3D optical vortex lattices open new possibilities for light-matter interactions and the related applications.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

12.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Sadreev A. F., Sherman, E. Ya.
Заглавие : Temporal oscillations of light transmission through dielectric microparticles subjected to optically induced motion
Коллективы : Russian Science Foundation [14-12-00266]; University of the Basque Country UPV/EHU (MINECO/FEDER) [UFI 11/55, FIS2015-67161-P]; Grupos Consolidados UPV/EHU del Gobierno Vasco [IT-472-10]
Место публикации : Phys. Rev. A: American Physical Society, 2016. - Vol. 94, Is. 3. - Ст.033820. - ISSN 2469-9926, DOI 10.1103/PhysRevA.94.033820. - ISSN 2469-9934(eISSN)
Примечания : Cited References:37. - The work of A.F.S. was partially supported by Grant No. 14-12-00266 from the Russian Science Foundation. This work of E.Y.S. was supported by the University of the Basque Country UPV/EHU under Program No. UFI 11/55, FIS2015-67161-P (MINECO/FEDER), and Grupos Consolidados UPV/EHU del Gobierno Vasco (Grant No. IT-472-10).
Предметные рубрики: FOCUSED LASER-BEAM
CAVITY OPTOMECHANICS
BACK-ACTION
FORCES
NANOPARTICLES
MANIPULATION
PARTICLES
TRAP
Аннотация: We consider light-induced binding and motion of dielectric microparticles in an optical waveguide that gives rise to a backaction effect such as light transmission oscillating with time. Modeling the particles by dielectric slabs allows us to solve the problem analytically and obtain a rich variety of dynamical regimes both for Newtonian and damped motion. This variety is clearly reflected in temporal oscillations of the light transmission. The characteristic frequencies of the oscillations are within the ultrasound range of the order of 105 kHz for micron-size particles and injected power of the order of 100mW. In addition, we consider dynamics of a dielectric particle, driven by light propagating inside a Fabry-Perot resonator. These phenomena pave a way for optical driving and monitoring of the motion of particles in waveguides and resonators.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

13.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Polyakov V. V., Polyakova K. P., Seredkin V. A., Zharkov S. M.
Заглавие : Synthesis and magneto-optical properties of nanogranular Co-Ti-O films
Коллективы : Russian Foundation for Basic Research [06-03-32970, 07-03-00190a]
Место публикации : Phys. Solid State. - 2009. - Vol. 51, Is. 9. - P.1866-1869. - ISSN 1063-7834, DOI 10.1134/S1063783409090169
Примечания : Cited References: 10. - This study was supported by the Russian Foundation for Basic Research (project nos. 06-03-32970 and 07-03-00190a).
Предметные рубрики: HIGH-TEMPERATURE SYNTHESIS
THIN-LAYERS
PARTICLES
Аннотация: Studies of the structural and magneto-optical properties of nanogranular Co-Ti-O films prepared under conditions of the solid-state reaction with oxygen exchange in the CoO/Ti layered structures are presented. The formation of granular films with compositions near or below the percolation threshold is shown. The specific features of the magneto-optical spectra of the prepared films as compared to the spectra of continuous metallic films are revealed.
WOS,
Читать в сети ИФ
Найти похожие

14.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Sadreev A. F.
Заглавие : Enhancement of Rayleigh scattering in a two-dimensional Fabry-Perot resonator loaded with impurities
Коллективы : Russian Science Foundation (RSF) [14-12-00266]
Место публикации : J. Opt. Soc. Am. A: Optical Society of America, 2016. - Vol. 33, Is. 7. - P.1277-1282. - ISSN 1084-7529, DOI 10.1364/JOSAA.33.001277. - ISSN 1520-8532(eISSN)
Примечания : Cited References:32. - Russian Science Foundation (RSF) (14-12-00266)
Предметные рубрики: COUPLED-MODE THEORY
MULTIPLE-SCATTERING
NUCLEAR REACTIONS
UNIFIED THEORY
RANDOM-MEDIA
TRANSMISSION
PARTICLES
WAVES
LIGHT
STRIP
Аннотация: We study wave transmission through a Fabry-Perot resonator (FPR) loaded with point-like impurities. We show both analytically in the framework of the coupled mode theory and numerically that there are two different regimes for transmission dependent on the quality of the FPR mirrors. For low quality, we obtain transmittance very similar to the clean FPR with slightly shifted Lorentz peaks. However, for good quality, the transmittance peaks are strongly reduced and substituted with Gaussian peaks because of multiple scattering of waves by each impurity. As a side effect, we observe the angular (channel) conversion in the disordered FPR. We demonstrate that the resonant peaks are dependent on the concentration of impurities to pave a way for resonant measurement of the concentration. (C) 2016 Optical Society of America
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

15.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Bulgakov E. N., Maksimov D. N.
Заглавие : Light guiding above the light line in arrays of dielectric nanospheres
Место публикации : Opt. Lett.: Optical Society of America, 2016. - Vol. 41, Is. 16. - P.3888-3891. - ISSN 01469592 (ISSN), DOI 10.1364/OL.41.003888
Примечания : Cited References: 46. - Russian Foundation for Basic Research (RFBR) (16-02-00314).
Предметные рубрики: SUBWAVELENGTH WAVE-GUIDES
OPTICAL MODES
NANOPARTICLES
CHAINS
RESONANCES
PARTICLES
SPHERES
Аннотация: We consider light propagation above the light line in arrays of spherical dielectric nanoparticles. It is demonstrated numerically that quasi-bound leaky modes of the array can propagate both stationary waves and light pulses to a distance of 60 wavelengths at the frequencies close to the bound states in the radiation continuum. A semi-analytical estimate for decay rates of the guided waves is found to match the numerical data to a good accuracy. © 2016 Optical Society of America.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

16.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Karpov S. V., Semina P. N., Gavrilyuk A. P.
Заглавие : The role of the electron tunneling effect in the coagulation kinetics of polydisperse metal nanocolloids
Место публикации : Colloid J.: MAIK Nauka-Interperiodica / Springer, 2012. - Vol. 74, Is. 3. - P.305-312. - ISSN 1061-933X, DOI 10.1134/S1061933X12030052
Примечания : Cited References: 16. - Authors are thankful to G. A. Chiganova for discussions and helpful comments. Studies were carried out with the support of grants: the Presidium of RAS No 29 and No 31, OFN RAS III.9.5, IP SB RAS No 43, IP SB RAS (and SFU) No 101.
Предметные рубрики: PARTICLES
Аннотация: The energy of pair interactions between metal nanoparticles of different sizes is shown to be able to increase upon coagulation due to the additional electrostatic effect resulting from mutual heteropolar charging of the particles. The tunnel electron transfer occurring upon the collisions between particles of different sizes may be the reason for the charging. The transfer is caused by the dependence of the electron work function on the particle size. The electron transfer through the interparticle gap equalizes the Fermi levels in particles of different sizes and is associated with this dependence. Using the example of bimodal silver nanocolloids, it is shown that mutual heteropolar charging of particles with different sizes may accelerate the coagulation of polydisperse colloidal systems by an order of magnitude or more as compared with monodisperse systems, in which this effect is absent.
Смотреть статью,
Scopus,
WoS,
Читать в сети ИФ
Найти похожие

17.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Atuchin V. V., Bekenev V. L., Chimitova O. D., Molokeev M. S., Bazarov B. G., Bazarova J. G., Khuzhum O. Y., Lim C. S.
Заглавие : Synthesis and electronic properties of β-RbNd(MoO4)2
Место публикации : Asian J. Chem. - 2014. - Vol. 26, No. 5. - P.1284-1286. - ISSN 0970-7077, DOI 10.14233/ajchem.2014.17209
Примечания : Cited References: 26. - This study is partly supported by by the Ministry of Education and Science of the Russian Federation.
Предметные рубрики: UP-CONVERSION PHOTOLUMINESCENCE
VIBRATIONAL PROPERTIES
CRYSTAL-STRUCTURE
PARTICLES
MOLYBDATE
SPECTROSCOPY
SYSTEM
ER3+
Ключевые слова (''Своб.индексиров.''): β-rbnd(moo4)2--electronic structure--ab initio calculations--x-ray photoelectron spectroscopy
Аннотация: The electronic structure of β-RbNd(MoO4)2 has been evaluated from experimental and theoretical points of view. For the molybdate, X-ray photoelectron valence-band spectra have been measured. The total and partial densities of states of the constituent atoms of β-RbNd(MoO4)2 have been calculated using the FP-LAPW method. The FP-LAPW data reveal that main contributors in the valence-band region of β-RbNd(MoO4)2 are the Rb 4p-, Nd 4f-, Mo 4d- and O 2p-like states.
Смотреть статью,
Scopus,
WoS,
Читать в сети ИФ
Найти похожие

18.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kirillov V. L., Balaev D. A., Semenov S. V., Shaikhutdinov K. A., Martyanov O. N.
Заглавие : Size control in the formation of magnetite nanoparticles in the presence of citrate ions
Коллективы : Siberian Branch of the Russian Academy of Sciences
Место публикации : Mater. Chem. Phys.: Elsevier Science, 2014. - Vol. 145, Is. 1-2. - P.75-81. - ISSN 0254-0584, DOI 10.1016/j.matchemphys.2014.01.036. - ISSN 1879-3312
Примечания : Cited References: 46. - This work was supported by the Interdisciplinary Integration Project no. 45 of the Siberian Branch of the Russian Academy of Sciences for 2012-2014.
Предметные рубрики: OLEIC-ACID
CATALYST
HYPERTHERMIA
PARTICLES
OXIDATION
REMOVAL
CO
Ключевые слова (''Своб.индексиров.''): magnetic materials--magnetic properties--precipitation--electron paramagnetic resonance
Аннотация: A one-pot synthesis method for the controllable growth of magnetite nanoparticles directly during the process of co-precipitation using citrate ions was developed. The effects of the concentration of citrate ions and the solution pH on the characteristics of magnetite particles with sizes in the range of 4-10 nm synthesized by the method of co-precipitation were studied. The results showed that the specified concentration of citrate ions allowed the preparation of magnetite particles with a definite size that exhibited superparamagnetic behaviour in a particular temperature range. As the concentration ratio of citrate to iron ions was increased from 0 to 0.11, the average size of the prepared magnetite particles decreased from 10.5 to 4.4 nm. As a result, the superparamagnetic blocking temperature decreased from 300 to 20 K, the saturation magnetisation decreased from 50 to 20 emu g(-1), and the average magnetic moment decreased from 8000 mu(B) to 340 mu(B) (at T = 300 K). The obtained experimental data proved that the size effects of the magnetite nanoparticles can be attributed to the capping of the magnetite surface by adsorbed citrate ions. Thus, the suggested approach allows magnetite nanoparticles to be prepared with an optimum particle size around superparamagnetic threshold that prevents their irreversible agglomeration and simultaneously allows them to be removed from a solution at an acceptable rate. (C) 2014 Elsevier B.V. All rights reserved.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

19.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Ershov A. E., Isaev I. L., Semina P. N., Markel V. A., Karpov S. V.
Заглавие : Effects of size polydispersity on the extinction spectra of colloidal nanoparticle aggregates
Место публикации : Phys. Rev. B: American Physical Society, 2012. - Vol. 85, Is. 4. - Ст.045421. - P. - ISSN 1098-0121, DOI 10.1103/PhysRevB.85.045421
Примечания : Cited References: 41. - This work was supported by grants from the following foundations of the Russian Federation: Presidium of RAS, OFN RAS, and SB RAS.
Предметные рубрики: METAL FRACTAL CLUSTERS
OPTICAL-PROPERTIES
ABSORPTION
NONLINEARITIES
COMPOSITES
SCATTERING
PARTICLES
SPHERES
GRAINS
Аннотация: We investigate the effect of particle polydispersity on the optical extinction spectra of colloidal aggregates of spherical metallic (silver) nanoparticles, taking into account the realistic interparticle gaps caused by layers of stabilizing polymer adsorbed on the metal surface (adlayers). The spectra of computer-generated aggregates are computed using two different methods. The coupled-multipole method is used in the quasistatic approximation and the coupled-dipole method beyond the quasistatics. The latter approach is applicable if the interparticle gaps are sufficiently wide relative to the particle radii. Simulations are performed for two different particle size distribution functions (bimodal and Gaussian), varying the number of particles per aggregate, and different distribution functions of the interparticle gap width. The strong influence of the latter factor on the spectra is demonstrated and investigated in detail.
Смотреть статью,
Scopus,
WoS,
Читать в сети ИФ
Найти похожие

20.

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Safronov A. P., Beketov I. V., Komogortsev S. V., Kurlyandskaya G. V., Medvedev A. I., Leiman D. V., Larranaga A., Bhagat S. M.
Заглавие : Spherical magnetic nanoparticles fabricated by laser target evaporation
Место публикации : AIP Adv.: American Institute of Physics, 2013. - Vol. 3, Is. 5. - Ст.052135. - P. - ISSN 2158-3226, DOI 10.1063/1.4808368
Примечания : Cited References: 47. - This work was supported by the RFBR 10-02-96015 and 12-02-31385 projects, UrFU 215, Spanish MEC MAT2011-27573-C04 grants, Universidad del Pais Vasco UPV/EHU under UFI11/53 action and Physics Department of the University of Maryland visiting grant. Selected measurements were performed at SGIker service of UPV-EHU. We thank O.M. Samatov, Dr. A.M. Murzakayev, Dr. I. Orue, and A.A. Svalova for special support.
Предметные рубрики: IRON-OXIDE NANOPOWDERS
CO2-LASER EVAPORATION
FE3O4 NANOPARTICLES
FINITE-SIZE
TEMPERATURE
FERROMAGNETS
FERROFLUIDS
DEPENDENCE
EXPLOSION
PARTICLES
Аннотация: Magnetic nanoparticles of iron oxide (MNPs) were prepared by the laser target evaporation technique (LTE). The main focus was on the fabrication of de-aggregated spherical maghemite MNPs with a narrow size distribution and enhanced effective magnetization. X-ray diffraction, transmission electron microscopy, magnetization and microwave absorption measurements were comparatively analyzed. The shape of the MNPs (mean diameter of 9 nm) was very close to being spherical. The lattice constant of the crystalline phase was substantially smaller than that of stoichiometric magnetite but larger than the lattice constant of maghemite. High value of M-s up to 300 K was established. The 300 K ferromagnetic resonance signal is a single line located at a field expected from spherical magnetic particles with negligible magnetic anisotropy. The maximum obtained concentration of water based ferrofluid was as high as 10g/l of magnetic material. In order to understand the temperature and field dependence of MNPs magnetization, we invoke the core-shell model. The nanoparticles is said to have a ferrimagnetic core (roughly 70 percent of the caliper size) while the shell consists of surface layers in which the spins are frozen having no long range magnetic order. The core-shell interactions were estimated in frame of random anisotropy model. The obtained assembly of de-aggregated nanoparticles is an example of magnetic nanofluid stable under ambient conditions even without an electrostatic stabilizer. (C) 2013 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.
Смотреть статью,
WoS,
WOS,
Читать в сети ИФ
Найти похожие