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Каталог книг и брошюр библиотеки ИФ СО РАН

Каталог журналов библиотеки ИФ СО РАН

Труды сотрудников ИФ СО РАН

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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Mikhlin Y., Vorobyev S., Romanchenko A., Karasev S., Karacharov A., Zharkov S. M.
Заглавие : Ultrafine particles derived from mineral processing: A case study of the Pb-Zn sulfide ore with emphasis on lead-bearing colloids
Место публикации : Chemosphere: Elsevier, 2016. - Vol. 147. - P.60-66. - ISSN 00456535 (ISSN), DOI 10.1016/j.chemosphere.2015.12.096
Примечания : Cited References: 47. - This research was supported by the Russian Science Foundation, Grant No. 14-17-00280.
Предметные рубрики: GALENA DISSOLUTION
METALLIC COPPER
NANOPARTICLES
SOIL
ENVIRONMENT
SEPARATION
TRANSPORT
FLOTATION
WATER
SIZE
Ключевые слова (''Своб.индексиров.''): lead sulfide--lead-zinc ore--lead sulfide--ultrafine particles--aquatic nanoparticles
Аннотация: Although mining and mineral processing industry is a vast source of heavy metal pollutants, the formation and behavior of micrometer- and nanometer-sized particles and their aqueous colloids entered the environment from the technological media has received insufficient attention to date. Here, the yield and characteristics of ultrafine mineral entities produced by routine grinding of the Pb-Zn sulfide ore (Gorevskoe ore deposit, Russia) were studied using laser diffraction analysis (LDA), dynamic light scattering (DLS) and zeta potential measurement, microscopy, X-ray photoelectron spectroscopy, with most attention given to toxic lead species. It was revealed, in particular, that the fraction of particles less that 1 ?m in the ground ore typical reaches 0.4 vol. %. The aquatic particles in supernatants were micrometer size aggregates with increased content of zinc, sulfur, calcium as compared with the bulk ore concentrations. The hydrodynamic diameter of the colloidal species decreased with time, with their zeta potentials remaining about -12 mV. The colloids produced from galena were composed of 20-50 nm PbS nanoparticles associated with lead sulfate and thiosulfate, while the surface oxidation products at precipitated galena were largely lead oxyhydroxides. The size and zeta potential of the lead-bearing colloids decreased with time down to about 100 nm and from -15 mV to -30 mV, respectively. And, conversely, lead sulfide nanoparticles were mobilized before the aggregates during redispersion of the precipitates in fresh portions of water. The potential environmental impact of the metal-bearing colloids, which is due to the large-scale production and relative stability, is discussed. © 2015 Elsevier Ltd.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Karpov S. V., Gerasimov V. S., Isaev I. L., Markel V. A.
Заглавие : Spectroscopic studies of fractal aggregates of silver nanospheres undergoing local restructuring
Место публикации : J. Chem. Phys.: AMER INST PHYSICS, 2006. - Vol. 125, Is. 11. - Ст.111101. - ISSN 0021-9606, DOI 10.1063/1.2229202
Примечания : Cited References: 30
Предметные рубрики: ENHANCED RAMAN-SCATTERING
SMALL-PARTICLE COMPOSITES
OPTICAL-PROPERTIES
DISORDERED CLUSTERS
NONLINEAR OPTICS
LOCALIZATION
NANOPARTICLES
EIGENMODES
BOUNDS
Ключевые слова (''Своб.индексиров.''): large-scale fractal geometry--nonlinear optical responses--restructuring--silver nanospheres--aggregates--colloids--electromagnetic fields--fractals--nonlinear optics--sampling--spectroscopic analysis--silver
Аннотация: We present an experimental spectroscopic study of large random colloidal aggregates of silver nanoparticles undergoing local restructuring. We argue that such well-known phenomena as strong fluctuation of local electromagnetic fields, appearance of "hot spots" and enhancement of nonlinear optical responses depend on the local structure on the scales of several nanosphere diameters, rather than the large-scale fractal geometry of the sample. (c) 2006 American Institute of Physics.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Shalaev V. M., Poliakov E. Y., Markel V. A.
Заглавие : Small-particle composites .2. Nonlinear optical properties
Место публикации : Phys. Rev. B: AMERICAN PHYSICAL SOC, 1996. - Vol. 53, Is. 5. - P2437-2449. - ISSN 0163-1829, DOI 10.1103/PhysRevB.53.2437
Примечания : Cited References: 45
Предметные рубрики: FRACTAL CLUSTERS
RAMAN-SCATTERING
SUSCEPTIBILITY
CONDUCTIVITY
EXCITATIONS
COLLOIDS
LIGHT
Аннотация: Strong fluctuations of local fields may result in very large optical nonlinearities in small-particle composites. Enhancement associated with particle clustering is found for a number of optical processes, including four-wave mixing (FWM), third-harmonic generation (THG), Raman scattering, and nonlinear refraction and absorption in Kerr media. Field fluctuations and optical nonlinear susceptibilities are especially large in fractal clusters. The enhancement of optical processes is expressed in terms of the resonant linear absorption by collective dipolar eigenmodes in a cluster, and quality factors, q, of the modes (q much greater than 1). It is shown that the susceptibility of a composite material consisting of random small-particle clusters is proportional to q(3) for Raman scattering and the Kerr optical nonlinearity, and to q(4) and q(6) for THG and FWM, respectively. For all of these processes, a spectral dependence of the effective susceptibility is found. Broad-scale numerical simulations of the optical response in small-particle composites are performed to complement the theory. The simulations are in reasonable agreement with available experimental data.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Mikhlin Y., Romanchenko A., Vorobyev S., Karasev S., Volochaev M. N., Kamenskiy E., Burdakova E.
Заглавие : Ultrafine particles in ground sulfide ores: A comparison of four Cu-Ni ores from Siberia, Russia
Место публикации : Ore Geol. Rev.: Elsevier, 2017. - Vol. 81, Part 1. - P.1-9. - ISSN 0169-1368, DOI 10.1016/j.oregeorev.2016.10.024
Примечания : Cited References: 64. - This research was supported by the Russian Science Foundation, grant no. 14-17-00280.
Ключевые слова (''Своб.индексиров.''): cu-ni sulfide ores--ultrafine particles--mineral surfaces--colloids--beneficiation--environment
Аннотация: Nano-, submicro- and micrometer mineral particles may have an important role in beneficiation of metal ores and environmental impact, but their origin and characteristics are poorly understood. Here, we report data for the yield and the composition of fine fractions, and surfaces of several ground Cu-Ni sulfide ores studied using laser diffraction, scanning electron microscopy and energy dispersive X-ray analysis, X-ray photoelectron spectroscopy. Colloidal particles were characterized using dynamic light scattering, zeta-potential measurement, transmission electron microscopy and electron diffraction. The production of fines by dry milling was found to increase from about 0.01 vol.% to 0.2 vol.% for submicrometer particles and from ~ 0.5 vol.% to about 1.5 vol.% for particulate material less than 5 μm in the following order: Noril'sk disseminated low sulfide ore ≤ Noril'sk Cu-rich sulfide ore < Noril'sk valleriite ore < Kingash ore. For wet milling, the yield may be several times higher. Both surfaces of the milled ores and colloids were enriched in O, Mg, Si (largely as serpentine slimes) and depleted in sulfur, basic metals and iron, but colloidal valleriite, chalcopyrite, and oxidized pyrrhotite were found in the respective supernatants too. Typically, the colloidal particles form aggregates with an average hydrodynamic diameter of about 1 μm and a smaller number of ~ 5 μm species, except for valleriite ore, which exhibits a single size distribution peak at 2.7 μm. Zeta-potential, which characterizes the electric charge of the particles and dispersion stability of colloids, changed from − 25 mV for the low sulfide ore to about 0 mV for valleriite ore, and to + 15 mV for Kingash ore. Poor flotation recovery of metal from Kingash ore and Noril'sk valleriite ore is suggested to be due to both the large quantities and positive charge of hydrophilic ultrafine serpentine and/or magnesium hydroxide minerals. Resistance to oxidation and hence stability against aggregation of copper-bearing sulfide colloids in waste waters is expected to result in a negative impact on the environment.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Tsipotan A. S., Gerasimova M. A., Aleksandrovsky A. S., Zharkov S. M., Slabko V. V.
Заглавие : Effect of visible and UV irradiation on the aggregation stability of CdTe quantum dots
Место публикации : J. Nanopart. Res.: Springer, 2016. - Vol. 18, Is. 11. - P.324-8. - ISSN 13880764 (ISSN), DOI 10.1007/s11051-016-3638-0
Примечания : Cited References: 23
Ключевые слова (''Своб.индексиров.''): nanotechnology--quantum dots--photostimulated aggregation--photostability--colloids--laser-induced self-assembly
Аннотация: The possibility of controlling the aggregation stability of CdTe quantum dots (QDs) stabilized by thioglycolic acid (TGA) is important for implementation of quasi-resonant laser-induced self-assembly. This study examines the influence of irradiation by the UV as well as by the visible light on the photostimulated aggregation of QDs. Different photochemical mechanisms are identified, depending on whether light wavelength falls into an interband transition or the first exciton transition. Irradiation by visible light does not lead to changes in the absorption spectra but decreases luminescence intensity through the detachment of TGA and the formation of dangling bonds, leading to the creation of radiativeless relaxation centers. UV irradiation (in the 300–370 nm range), at an intensity of 0.4 W/cm2, initially (during the first 75 min) leads to the degradation of the stabilizer and QDs’ surface. After 75 min of combined UV and visible light irradiation, a gradual increase in spontaneous aggregation takes place, testifying excessive decrease in stabilizing potential barrier height. Hence, the laser-induced self-assembly of CdTe QDs is recommended to be performed over a time period of between 80 and 100 min after the beginning of low-intensity UV irradiation under conditions equivalent to those applied in this study. © 2016, Springer Science+Business Media Dordrecht.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Lee W., De Araujo C. B., Khanarian G., Zyryanov V. Ya.
Заглавие : Feature issue introduction: Colloidal systems
Место публикации : Opt. Mater. Express: Optical Society of America, 2017. - Vol. 7, Is. 2. - P.654-657. - ISSN 21593930 (ISSN), DOI 10.1364/OME.7.000654
Примечания : Cited References: 7
Ключевые слова (''Своб.индексиров.''): semiconductor quantum dots--colloidal materials--colloidal particle--colloidal solutions--device performance--photonic application--photonic properties--polymer composite--scientific discovery--colloids
Аннотация: This feature issue on "Colloidal Systems" of Optical Materials Express highlights recent advances in a broad scope of colloidal particles and structures. It consists of seven papers primarily in the areas of metal colloids, polymer composites and quantum dots in colloidal solutions. It is hoped that this special theme issue can urge and stimulate further research endeavors into novel colloidal materials with improved optical or photonic properties to accelerate scientific discoveries in the field of optical colloids, thereby promoting their structural and device performance for potential photonic applications. © 2017 Optical Society of America.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Vorobyev S., Likhatski M., Romanchenko A., Maksimov N., Zharkov S. M., Krylov A. S., Mikhlin Y.
Заглавие : Colloidal and deposited products of the interaction of tetrachloroauric acid with hydrogen selenide and hydrogen sulfide in aqueous solutions
Место публикации : Minerals. - 2018. - Vol. 8, Is. 11. - Ст.492. - ISSN 2075163X (ISSN), DOI 10.3390/min8110492
Примечания : Cited References: 63. - This research was funded by the Siberian Branch of the Russian Academy of sciences, Program of Interdisciplinary Studies, grant number 64 (project 303).
Ключевые слова (''Своб.индексиров.''): gold selenide--gold sulfoselenide--colloids--nanoparticles--nucleation--liquid intermediates--deposition
Аннотация: The reactions of aqueous gold complexes with H2Se and H2S are important for transportation and deposition of gold in nature and for synthesis of AuSe-based nanomaterials but are scantily understood. Here, we explored species formed at different proportions of HAuCl4, H2Se and H2S at room temperature using in situ UV-vis spectroscopy, dynamic light scattering (DLS), zeta-potential measurement and ex situ Transmission electron microscopy (TEM), electron diffraction, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Metal gold colloids arose at the molar ratios H2Se(H2S)/HAuCl4 less than 2. At higher ratios, pre-nucleation “dense liquid” species having the hydrodynamic diameter of 20–40 nm, zeta potential −40 mV to −50 mV, and the indirect band gap less than 1 eV derived from the UV-vis spectra grow into submicrometer droplets over several hours, followed by fractional nucleation in the interior and coagulation of disordered gold chalcogenide. XPS found only one Au+ site (Au 4f7/2 at 85.4 eV) in deposited AuSe, surface layers of which partially decomposed yielding Au0 nanoparticles capped with elemental selenium. The liquid species became less dense, the gap approached 2 eV, and gold chalcogenide destabilized towards the decomposition with increasing H2S content. Therefore, the reactions proceed via the non-classical mechanism involving “dense droplets” of supersaturated solution and produce AuSe1−xSx/Au nanocomposites.
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Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Omelyanchik A., Kamzin A. S., Valiullin A. A., Semenov V. G., Vereshchagin S. N., Volochaev M. N., Dubrovskiy A. A., Sviridova T., Kozenkov I., Dolan E., Peddis D., Sokolov A. Е., Rodionova V.
Заглавие : Iron oxide nanoparticles synthesized by a glycine-modified coprecipitation method: Structure and magnetic properties
Место публикации : Colloids Surf. A Physicochem. Eng. Asp. - 2022. - Vol. 647. - Ст.129090. - ISSN 09277757 (ISSN), DOI 10.1016/j.colsurfa.2022.129090
Примечания : Cited References: 80. - This work was supported by the Russian Science Foundation grant No. 21-72-20158 . The study of the structure was carried out on the equipment of the Center Collective Use " Materials Science and Metallurgy " which was purchased with the financial support of the Russian Federation represented by the Ministry of Education and Science (No. 075-15-2021-696)
Аннотация: Iron oxide magnetic nanoparticles (MNPs) are of interest in biomedicine and research owing to their moderate cytotoxicity and advanced properties, such as extensive surface-to-volume ratio and possibilities for tailoring their functionality through surface chemistry. To date, various approaches have been used for the synthesis of MNPs with controllable structural properties and various coatings to enhance their stability and functionality. This study describes a modified one-step method of coprecipitation in the presence of glycine allowing the production of particles with controllable size and in situ surface decoration. The effect of different glycine concentrations on the morphostructural and magnetic properties of iron oxide MNPs is studied. The particle size is reduced from 10.2 ± 0.3 to 7.2 ± 0.5 nm by increasing the glycine concentration from 0.06 up to 0.60 mol. The magnetic properties of obtained particles were tracked by SQUID magnetometry and Mossbauer spectroscopy. All samples of glycine capped iron oxide MNPs showed superparamagnetic behaviour at room temperature with maximal value of the saturation magnetization of 69 ± 4 Am2/kg. The results show the optimal concentration range of glycine which can be used in this method: a lower concertation than 0.15 mol does not affect the properties of obtained particles while higher concentrations than 0.3 mol lead to the reduction of magnetic properties (the saturation magnetisation reduces to 59 ± 3 Am2/kg when glycine concentration was 0.6 mol). The proposed economic and environment-friendly approach can be utilized to synthesise –NH2 functionalised MNPs for biomedical or wastewater treatment.
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