Dynamics of pH-sensitive nitroxide radicals in water adsorbed in ordered mesoporous molecular sieves by EPR Spectroscopy
Электронный архив УГЛТУ
Информация об архиве | Просмотр оригинала| Поле | Значение | |
| Заглавие |
Dynamics of pH-sensitive nitroxide radicals in water adsorbed in ordered mesoporous molecular sieves by EPR Spectroscopy
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| Автор |
Kovaleva, E. G.
Molochnikov, L. S. Golovkina, E. L. Hartmann, M. Kirilyuk, A. I. Grigorev, A. I. |
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| Тематика |
EPR SPECTROSCOPY
FAST (SLOW) RADICAL MOTION ORDERED MESOPOROUS MATERIALS PH-SENSITIVE NITROXIDE RADICALS ELECTRICAL POTENTIAL EPR SPECTROSCOPY FAST (SLOW) RADICAL MOTION MESOPOROUS MOLECULAR SIEVES NITROXIDE RADICALS ORDERED MESOPOROUS ORDERED MESOPOROUS MATERIALS ROTATIONAL CORRELATION TIME ACIDITY MESOPOROUS MATERIALS MOLECULAR SIEVES PARAMAGNETIC RESONANCE ELECTRON SPIN RESONANCE SPECTROSCOPY |
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| Описание |
A spin pH probe technique was used to study the influence of the channel diameter on the EPR spectra of pH-sensitive nitroxide radicals (NR) located in the channels of the mesoporous molecular sieves MCM-41 and SBA-15 with diameters ranging from 2.3 to 8.1 nm. From EPR spectra analysis and the results of the NR retention by the mesoporous molecular sieves upon washing with an aqueous KCl solution, the regularities of NR molecular location inside the channels were studied. The obtained dependence of the fraction of the radical molecules in the fast motional regime (with the rotational correlation times, τc = 2 × 10-11 s-9 × 10-11s) in the channels of the mesoporous molecular sieves as a function of pH indicates that both NR in the fast and slow motional regime (with τc = 8 × 10 -9s-7 × 10-10s) may be used for estimation of the solution acidity inside the channels and of the near-surface electrical potential. © 2013 Elsevier Inc. All rights reserved.
This work was supported by the Research Program of the Ministry of the Education of the Russian Federation (2007-2011). E.G.K. thanks the Program of Cooperation “Mikhail Lomonosov” between the Ministry of Education of Russian Federation and the German Service of Academic Exchanges (DAAD). We are grateful to Dr. G. Chandrasekar for assistance in the synthesis of MMS and their characterization. Appendix A |
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| Дата |
2019-09-20T15:19:00Z
2019-09-20T15:19:00Z 2013 |
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| Тип |
Article
Journal article (info:eu-repo/semantics/article) Published version (info:eu-repo/semantics/publishedVersion) |
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| Идентификатор |
Kovaleva, E. G. Dynamics of pH-sensitive nitroxide radicals in water adsorbed in ordered mesoporous molecular sieves by EPR Spectroscopy / E. G. Kovaleva, L. S. Molochnikov, E. L. Golovkina [et al.] // Microporous and Mesoporous Materials. – 2013. – Vol. 179. – P. 258-264.
1387-1811 https://elar.usfeu.ru/handle/123456789/8815 |
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| Язык |
en
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| Права |
Restricted accedd (info:eu-repo/semantics/restrictedAccess)
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| Издатель |
Elsevier Science Publishing Company
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| Источник |
Microporous and Mesoporous Materials
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