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

Формат представления найденных документов:
полный	информационный	краткий

Отсортировать найденные документы по:
автору	заглавию	году издания	типу документа

Поисковый запрос: (<.>S=Adsorption<.>)

Общее количество найденных документов : 7
Показаны документы с 1 по 7

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kirik S. D., Parfenov V. A., Zharkov S. M.
Заглавие : Monitoring MCM-41 synthesis by X-ray mesostructure analysis
Место публикации : Micropor. Mesopor. Mater.: Elsevier Science, 2014. - Vol. 195. - P.21-30. - ISSN 1387-1811, DOI 10.1016/j.micromeso.2014.04.012. - ISSN 1873-3093
Примечания : Cited References: 70. - The investigation was made with financial support of the Program of Presidium RAS (Project 24.37), RF State contracts No 02.740.11.0629, RFBR Grants: 11-03-00610a and 11-03-12161-ofi, RSF 14-13-000025.
Предметные рубрики: ORDERED MESOPOROUS MATERIALS
ORDERED MESOPOROUS MATERIALS
IN-SITU
POWDER DIFFRACTION
SILICA/SURFACTANT COMPOSITES
ELECTRON-MICROSCOPY
MOLECULAR-SIEVES
STABLE MCM-41
SILICA
ADSORPTION
Ключевые слова (''Своб.индексиров.''): hydrothermal stability--mcm-41--mesostructure--tem--x-ray diffraction
Аннотация: The electron density maps calculated from X-ray diffraction patterns of the mesoporous silica material MCM-41 present averaged mesostructure images which in contrast to transmission electron microscopy (TEM) images are exceptionally repeating and represent the whole sample. It was shown that the averaged mesostructure parameters such as a unit cell parameter, a pore diameter, a wall width, a pore shape estimated from the X-ray powder diffraction data in combination with the continuous electron density function approach allow monitoring continuous set of the silica framework states at different stages of the material synthesis. The mentioned technique supplemented by N 2-adsorption measurements and transmission electron microscopy was applied for consideration of the MCM-41 hydrothermal stability. Attention has been given to the variations of the synthesis conditions affecting the hydrothermal stability, in particular the maintaining the basicity of the synthesis solution as well the substitution of the synthesis solution with water or a salt solution at hydrothermal treatment. The averaged pore shape was observed to be changed from cylindrical to hexagonal-prismatic form. The observed wall thickness was in the range from 0.75 to 1.25 nm. The competition of silica polycondensation and surface hydrolysis was shown to be responsible for the variety of framework geometry and hydrothermal stability. It has been established that the pore diameter increases generally due to the osmotic pressure of water. If the pores acquire the average prismatic hexagonal shape, the sample has low hydrothermal stability. Under the conditions favorable for the polycondensation the pores have averaged cylindrical shape and material demonstrates higher hydrothermal stability. Cooperative mechanism of mesostructure destruction under hydrothermal conditions was observed using TEM data and was discussed in connection with irregular polycondensation. © 2014 Elsevier Inc. All rights reserved.
Смотреть статью,
Scopus,
WoS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Mikhlin Y. L., Vorobyev S., Saikova S. V., Tomashevich Y., Fetisova O., Kozlova S., Zharkov S. M.
Заглавие : Preparation and characterization of colloidal copper xanthate nanoparticles
Коллективы : Russian Science Foundation [14-17-00280]
Место публикации : New J. Chem.: Royal Society of Chemistry, 2016. - Vol. 40, Is. 4. - P.3059-3065. - ISSN 1144-0546, DOI 10.1039/c6nj00098c. - ISSN 1369-9261(eISSN)
Примечания : Cited References:50. - This research was supported by the Russian Science Foundation grant 14-17-00280. We thank Dr Roberto Felix Duarte (HZB) and bilateral program "German-Russian laboratory at BESSY II" for assistance with the X-ray absorption experiments.
Предметные рубрики: X-ray-absorption
Self-assembled monolayers
Sulfide nanoparticles
Electronic-structure
Waste-water
Complexes
Flotation
Spectroscopy
Adsorption
Oxidation
Аннотация: Despite the important role of metal xanthates in a number of industrial processes and emerging applications, no attempts have been made to prepare the metal xanthate nanoparticles and to study colloidal solutions of insoluble heavy metal xanthates. Here, we examined the formation of colloidal copper xanthate particles during the reactions of aqueous solutions of cupric sulfate and various potassium xanthates, which occur in flotation and water treatment slurries and can be used to manufacture nanoparticles for materials science (e.g., as precursors for copper sulfide nanoparticles and biomedicine). The products were characterized using UV-vis absorption, dynamic light scattering, zeta potential measurements, transmission electron microscopy (TEM), electron diffraction, Fourier transform infrared spectroscopy, thermogravimetry, X-ray photoelectron spectroscopy, and X-ray absorption spectroscopy (XANES). Colloidal copper xanthates with compositions of ROCSSCu (R = ethyl, isopropyl, butyl, isobutyl, and amyl groups), disordered structures and average diameters of 20–80 nm easily formed and aggregated and were stable for at least several hours, especially if excessive xanthate was used. The hydrodynamic diameters of the nanoparticles were smaller at lower temperatures. Dixanthogens, which were produced in the reactions along with ROCSSCu, seemed to promote nanoparticle aggregation and precipitated with the copper xanthate, affecting their thermal decomposition. The TEM micrographs and S K- and Cu K-edge XANES spectra revealed core/shell particle morphologies, likely with Cu(I) bonded to four S atoms in the core and reduced copper coordination in the shell.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Fedorov A. S., Sorokin P. B.
Заглавие : Density and thermodynamics of hydrogen adsorbed on the surface of single-walled carbon nanotubes
Место публикации : Phys. Solid State: MAIK NAUKA/INTERPERIODICA/SPRINGER, 2006. - Vol. 48, Is. 2. - P402-407. - ISSN 1063-7834, DOI 10.1134/S1063783406020351
Примечания : Cited References: 22
Предметные рубрики: MOLECULAR-DYNAMICS
ROOM-TEMPERATURE
STORAGE
ADSORPTION
H-2
TRANSITIONS
TUBES
Аннотация: A method is proposed for calculating the adsorption of hydrogen in single-walled carbon nanotubes. This method involves solving the Schrodinger equation for a particle (hydrogen molecule) moving in a potential generated by the surrounding hydrogen molecules and atoms forming the wall of the carbon nanotube. The interaction potential for hydrogen molecules is taken in the form of the Silvera-Goldman empirical potential, which adequately describes the experimental data on the interaction between H(2) molecules (including the van der Waals interaction). The interaction of hydrogen molecules with carbon atoms is included in the calculation through the Lennard-Jones potential. The free energy at a nonzero temperature is calculated with allowance made for the phonon contribution, which, in turn, makes it possible to take into account the correlations in the mutual arrangement of the neighboring molecules. The dependences of the total energy, the free energy, and the Gibbs thermodynamic potential on the applied pressure P and temperature T are calculated for adsorbed hydrogen molecules. These dependences are obtained for the first time with due regard for the quantum effects. The pressure and temperature dependences of the hydrogen density m(P, T) are also constructed for the first time.
WOS,
Scopus,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Паршин, Александр Михайлович, Сутормин, Виталий Сергеевич, Зырянов, Виктор Яковлевич, Шабанов, Василий Филиппович
Заглавие : Влияние ионного сурфактанта на энергию сцепления жидкого кристалла с поверхностью, исследованное с использованием магнитных пороговых полей перехода Фредерикса
Место публикации : Жидк. кристаллы и их практич. использ. - 2018. - Т. 18, № 3. - С. 59-66. - ISSN 1991-3966, DOI 10.18083/LCAppl.2018.3.59; Liq. Cryst. Appl. - ISSN 2499-9644
Примечания : Библиогр.: 25. - В. С. Сутормин благодарен РФФИ за поддержку исследований по гранту № 16-32-60036 мол_а_дк.
Предметные рубрики: WALL INTERFACE
TEMPERATURE-DEPENDENCE
NEMATIC DROPLETS
ADSORPTION
Ключевые слова (''Своб.индексиров.''): нематический жидкий кристалл--ионный сурфактант--энергия сцепления--магнитное поле--переход фредерикса--nematic liquid crystal--ionic surfactant--anchoring energy--magnetic field--freedericksz transition
Аннотация: Исследовано сцепление нематического жидкого кристалла 5ЦБ и 5ЦБ, допированного ионным сурфактантом ЦТАБ, в ячейках с плоскопараллельными ограничивающими поверхностями. Получены зависимости интенсивности проходящего лазерного излучения от величины магнитного поля для ячеек с различными толщинами слоя нематика при различных температурах. Из пороговых полей перехода Фредерикса определены значения полярной энергии сцепления жидкого кристалла с поверхностью. Изучено влияние ионного сурфактанта на энергию сцепления, установлено, что добавление в объем жидкого кристалла ионного сурфактанта ведет к ее ослаблению. Проведен анализ точности определения энергии сцепления на основе выражения, следующего из соотношения Рапини – Популара. Показано, что лучшее экспериментальное разрешение энергии сцепления достигается при использовании тонких слоев нематика, более сильных магнитных полей, а также слабого сцепления молекул жидкого кристалла с поверхностью.The coupling of nematic liquid crystal 5CB and 5CB doped with ionic surfactant CTAB in the cells with plane parallel interfaces was studied. For the cells with the varied nematic layer thickness at different temperatures, the dependencies of the passed laser radiation intensity on the magnetic field were obtained. From the threshold fields of Freedericksz transition, the polar anchoring energy of the liquid crystal to the surface was determined. The effect of the ionic surfactant on the anchoring energy was studied and it was found that the addition of the ionic surfactant to liquid crystal weakens the anchoring energy. The analysis of the accuracy of the anchoring energy determination based on the expression following from the Rapini - Popular relation was carried out. It was shown that the best experimental resolution of the anchoring energy is achieved when the thin nematic layers, stronger magnetic fields and weak anchoring of the liquid crystal molecules with the surface are used.
Смотреть статью,
РИНЦ,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Parshin A. M., Sutormin V. S., Zyryanov V. Ya., Shabanov V. F.
Заглавие : Polar anchoring energy and tilt angle measured by magneto-optical technique in nematic doped with ionic surfactant
Место публикации : Liq. Cryst. - 2020. - Vol. 47, Is. 12. - P.1825-1831. - ISSN 0267-8292, DOI 10.1080/02678292.2020.1733683. - ISSN 1366-5855(eISSN)
Примечания : Cited References: 32
Предметные рубрики: LIQUID-CRYSTAL
TEMPERATURE-DEPENDENCE
INTERFACE
ADSORPTION
Аннотация: The surface anchoring of a nematic doped with the ionic surfactant has been investigated and compared with the one in the undoped sample. The director tilt angle at the substrates coated with the orienting polymer film has been determined by the null method in a rotating magnetic field. The Frederiks transition in a magnetic field has been chosen as a convenient technique to measure the polar anchoring energy Wθ. The temperature dependences of anchoring energy have been obtained for the various nematic cells. The Wθ values for nematic doped with the ionic surfactant are less than for the undoped one. The factors affecting the measurement accuracy have been discussed. The accuracy is higher for the thinner nematic layers and weaker anchoring energy.
Смотреть статью,
Читать в сети ИФ,
Scopus,
WOS
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kremneva A. M., Fedorov A. V., Bulavchenko O. A., Knyazev Yu. V., Saraev A. A., Yakovlev V. A., Kaichev V. V.
Заглавие : Effect of calcination temperature on activity of Fe2O3-Al2O3 nanocomposite catalysts in CO oxidation
Коллективы : Russian Science FoundationRussian Science Foundation (RSF) [17-73-20157]; National center of investigation of catalysts" at Boreskov Institute of Catalysis
Место публикации : Catal. Lett. - 2020. - Vol. 150. - P.3377-3385. - ISSN 1011-372X, DOI 10.1007/s10562-020-03250-8. - ISSN 1572-879X(eISSN)
Примечания : Cited References: 31. - This work was supported by the Russian Science Foundation (Grant No. 17-73-20157). The experiments were performed using facilities of the shared research center "National center of investigation of catalysts" at Boreskov Institute of Catalysis. The authors thank A.Yu. Gladky for the TPR measurements and Z.S. Vinokurov for the XRD measurements.
Предметные рубрики: MOSSBAUER
SPECTROSCOPY
CHEMISTRY
IRON
XPS
ADSORPTION
OXYGEN
FE
Аннотация: Nanocomposite Fe–Al oxide catalysts were prepared by the melting of iron and aluminum nitrates with the subsequent calcination in air at different temperatures. It was found that the catalysts calcined at 450 °C are more active in the oxidation of CO than the catalysts calcined at 700 °C. X-ray diffraction and X-ray photoelectron spectroscopy showed that all the catalysts consist of hematite, α-Fe2O3 nanoparticles, and Al2O3 in an amorphous state. Iron oxide is the active component, which provides the oxidation of CO, while alumina is a texture promoter. The increase in the calcination temperature leads to a minor increase in the average size of hematite nanoparticles and an insignificant decrease in the specific surface area. Kinetic measurements showed that the oxidation of CO over the Fe–Al catalysts calcined at 450 and 700 °C proceeds with the activation energy of 61–69 and 91 kJ/mol, respectively. This means that the low-temperature and high-temperature catalysts contain different active species. Temperature-programmed reduction with CO indicated that the decrease in the calcination temperature improves the reducibility of the Fe-Al nanocomposites. According to 57Fe Mössbauer spectroscopy, the low-temperature catalysts contain hydrated iron oxides (acagenite and ferrihydrite) and a significant amount of highly defective hematite, which is absent in the high-temperature catalyst. These species can provide the enhanced activity of the low-temperature catalysts in the oxidation of CO.
Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Найти похожие

Вид документа : Статья из журнала
Шифр издания :
Автор(ы) : Kononova O.N., Melnikov A.M., Borisova T.V., Krylov A. S.
Заглавие : Simultaneous ion exchange recovery of platinum and rhodium from chloride solutions
Место публикации : Hydrometallurgy. - 2011. - Vol. 105, Is. 3-4. - P.341-349. - JAN. - ISSN 0304-386X, DOI 10.1016/j.hydromet.2010.11.009
Примечания : Cited Reference Count: 46
Предметные рубрики: GROUP-METALS PGM
SEPARATION
CATALYST
ANION
ADSORPTION
EXTRACTION
CHEMISTRY
RESIN
Ключевые слова (''Своб.индексиров.''): platinum--rhodium--sorption--anion exchangers--chloride solutions--anion exchangers--chloride solutions--platinum--rhodium--sorption--ammonium thiocyanate--anion exchangers--basic parameters--chemical structure--chloride solutions--diffusion coefficients--distribution coefficient--exchange capacities--kinetic properties--noble metals--purolite--rhodium chloride--separation factors--sorption ability--work focus--ammonium compounds--chlorine compounds--desorption--hydrochloric acid--ion exchange--ion exchange resins--ions--platinum--platinum compounds--potassium hydroxide--precious metals--recovery--rhodium--sulfuric acid--thioureas--urea--rhodium compounds
Аннотация: This work focuses on the sorption recovery of platinum (II, IV) and rhodium (III) simultaneously present in chloride solutions, freshly prepared and stored over 3 months, on commercial anion exchangers with different physical and chemical structure. The sorption was carried out from solutions with 0.001-4.0 mol/L HCl. The initial platinum and rhodium concentrations in contacting solutions were 0.25-2.5 mmol/L Sorption and kinetic properties of the chosen anion exchangers were investigated and the basic parameters of exchange capacity, recovery, distribution coefficients, separation factors, process rate, diffusion coefficients and half-exchange times were calculated. It is shown that anion exchangers investigated possess high sorption ability to platinum and rhodium chloride complexes, which does not deteriorate in case of stored solutions. Desorption of platinum and rhodium from the resins investigated was carried out with hydrochloric acid (2 mol/L), thiourea (1 mol/L) in sulfuric acid (2 mol/L) or in potassium hydroxide (2 mol/L) as well as by ammonium thiocyanate (2 mol/L). It was shown that complete separation of platinum and rhodium can be carried out with 2 mol/L HCl on anion exchanger Purolite S 985, whereas 2 mol/L NH(4)SCN as an elution agent leads to complete separation of noble metals on anion exchangers Purolite S 985, Purolite A 500 and AM-2B. (C) 2010 Elsevier B.V. All rights reserved.
WOS,
Scopus,
eLibrary
Найти похожие