Makunin A.V., Bukunov K.A., Vorobyeva E.A., Pankratov D.A., Petrov D.V., Chechenin N.G. Variation of Composition and Structure over the Height in Arrays of Vertically Aligned CNT. /XII International Conference on Nanostructured Materials (NANO 2014), July 13-18, 2014 Moscow, Russia (2014), pp01.116
Arrays of vertically aligned multiwall carbon nanotubes (MWNT) were grown by the method of pyrolitic gas-phase deposition were studied by a number of techniques. Vibrational modes variations over the length (height) of CNTs with abnormal large aspect ratio of the order of 104 ÷ 105 were studied using the Raman scattering spectra. The results made it possible to estimate structure degree of disorder variation over the length of MWNTs indirectly. Microstructure and composition data were obtained using scanning electron microscopy (SEM) and X-ray dispersion analysis. The method of Mössbauer spectrometry was used to investigate the phases of iron present in MWNTs. Based on the experimental results, various iron phases distribution influence on the MWNTs growth mechanism was discussed.
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Constrained growth of anisotropic magnetic δ-FeOOH nanoparticles in the presence of humic substances. Polyakov A.Yu., Goldt A.E., Sorkina T.A., Perminova I.V., Pankratov D.A., Goodilin E.A., Tretyakov Y.D. //CrystEngComm. 2012. V.14. №23. P.8097-8102.
Natural polyelectrolytes, humic substances, are suggested to control in situ growth of feroxyhyte nanoparticles of a highly reduced mean size and with enhanced colloidal stability in salt solutions. The feroxyhyte is formed as 2-5 nm thick and 20 × 20 nm wide nanoflakes due to the blocking of developing facets of feroxyhyte and constraints caused by diffusion limitations of ionic constituents across partially charged branches of humic substances.
Superparamagnetic iron oxide nanoparticles (SPIONs) are known as effective biocompatible agents for various biomedical applications like drug delivery, in vivo magnetic resonance imaging, cell and protein separation, hyperthermia and transfection. At present, synthesis and application of rods, disks, fibers, tubes, sheets, ellipsoids, dumbbell-shaped, acorn-shaped and other anisotropic nanoparticles attract growing attention because of their unique properties. Aggregation is a serious problem in the preparation and storage of such magnetic nanoparticles limiting considerably their practical applications. This problem can be solved by a surface modification of nanoparticles with organic macromolecules, their preparation in the presence of surfactants, application of hydrophilic, surface-active ligands improving biocompatibility and resulting in multifunctional nanoparticles for medical diagnostics.
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Результаты лабораторных испытаний фильтрующих композиций для комплексной очистки воды. Панкратов Д.А., Борисова Е.М., Воликов А.Б. //Водоочистка. 2015. №1. С.27-35.
This article presents the results of laboratory tests of four filtering materials, which are presented on the market of water treatment and intended for a complex water purification. It is shown that the data of static and dynamic tests are in good agreement with each other. All tested filtering materials demonstrated satisfactory results in sorption of hardness ions and iron ions from water. Blind tests which were provided by two independent laboratories showed that a maximum degree of water purification from iron ions and a maximum of sorption capacity, even after multiple cycles of regeneration, are observed for the filtering composition Multisorb which is intended for a complex water treatment.
В статье приводятся результаты лабораторных испытаний четырех фильтрующих композиций, представленных на рынке водообработки, и предназначенных для комплексной очистки воды. Показано, что данные статических и динамических испытаний хорошо согласуются между собой. Все испытанные фильтрующие композиции продемонстрировали удовлетворительные результаты по сорбции из воды ионов жесткости и ионов железа. В ходе слепого тестирования в двух независимых лабораториях показано, что максимальная степень очистки воды от ионов железа и сорбционная емкость, в том числе после многократных циклов регенерации, наблюдается для фильтрующей композиции Multisorb, предназначенной для комплексной очистки воды.
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Potassium hexahydroperoxostannate: synthesis and structure. Ippolitov E.G., Tripol'skaya T.A., Prikhodchenko P.V., Pankratov D.A. //Russian Journal of Inorganic Chemistry. 2001. V.46. №6. P.851-857
Polycrystalline potassium hexahydroperoxostannate was prepared by replacement of hydroxo groups in potassium hexahydroxostannate upon its dissolution in hydrogen peroxide. A comparative study of the product and the starting hydroxostannate by powder X-ray diffraction analysis, thermogravimetry, and IR, 2H, 39K, and 119Sn NMR, and Mössbauer spectroscopy was carried out. The peroxo compound K2Sn(OOH)6 crystallizes in the hexagonal system with a = 7.264(7) Å, c = 10.168(4) Å. IR, NMR, and Mössbauer spectroscopy data show that the tin coordination polyhedron in the peroxo compound is an octahedron formed by the coordinated hydroperoxo groups.
Previously, sodium hexahydroperoxostannate was prepared and characterized by powder X-ray diffraction analysis, thermogravimetry, IR, 1H NMR, and Mossbauer spectroscopy, and by thermodynamic and kinetic method. The tin atom in this compound were found to occur in the octahedral environment of hydroperoxo group. It appeared pertinent to confirm the possibility of formation of this type of tin compound by preparing a new hydroperoxo complex. To this end, we performed the first synthesis of potassium hexahydroperoxostannate. Comparative study of potassium hexahydrosstannate (1) and hexahydroperoxosstannate (2) and their deuterated analogue (1a and 2a, respectively) was carried out by powder X-ray diffraction analysis, thermogravimetry, and IR, NMR (2H, 39K and 119Sn), and Mossbauer spectroscopy.
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