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Some sorption and salt occlusion properties of silicalite-1Flynn, Tracey Karen January 1987 (has links)
No description available.
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Study Of Sorption Of Alcohols On High Silica Zsm-35Babuccuoglu, Yurdaer 01 January 2007 (has links) (PDF)
This study investigated the equilibrium sorption capacities and
rates of sorption of some alcohols on Na- and/or H- form of
ZSM-35 at different temperatures by gravimetric method using
an electrobalance. The alcohols studied were methanol, ethanol, propan-1-ol, propan-2-ol, n-butanol.
The ZSM-35 sample used in sorption experiments resulted from
a study for synthesis of high silica ZSM-35 zeolite. This ZSM-35 sample was called as NaZSM-35. The influence of ion-exchange on the sorption capacity and kinetics was investigated by converting NaZSM-35 into H-form by the ion exchange method. In this method, a sufficient amount of ZSM-35 sample (200-250 mg) was mixed with 25 ml of 1 N NH4Cl solution for 24 hours at room temperature. This procedure was repeated until no Na+ was detected by a Flame Photometer. After the ion exchange was completed , the sample was washed with deionized water, filtered, dried and recalcined for the removal of the ammonia and this sample was denoted as HZSM-35.
The highest sorption capacity (cm3/g) was observed for
methanol on HZSM-35 / 0.1656 cm3/g and the lowest sorption
capacity was observed for propan-2-ol at NaZSM-35 / 0.003
cm3/g. Sorption of methanol and ethanol were very rapid. The
sorption capacities of other three alcohols / propan-1-ol,
propan-2-ol and n-butanol, were lower and they had slower
rates of sorption.
HZSM-35 had greater limiting sorption capacity than NaZSM-35 for propan-1-ol, propan-2-ol and n-butanol at all temperatures.
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Vývoj a výzkum environmentálně úsporných izolačních materiálů / Development of environmental friendly materialsPeterková, Jitka January 2013 (has links)
Increasing demand for new progressive construction materials requires development of modern environmentally friendly materials with excellent end-use properties and reasonable price. One of the main objectives of material research in building industry is using renewable resources of raw materials of industrial waste for development of new construction materials. Current trend of thermal insulation of building constructions results in development of environmentally friendly insulation materials based on renewable material resources from agriculture and stock farming, which could became alternative for current common use insulation materials in the future. The thesis describes research and development of insulation materials based on natural fibres of agricultural origin; in particular fibres of hemp, flax and jute. Hydrothermal behavior of developed materials is studied including computational simulation of behavior of researched materials after building in the construction.
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Структура и сорбционные свойства плёнок на основе гидроксиэтилцеллюлозы и углеродных нанотрубок : магистерская диссертация / Structure and sorption properties of films based on hydroxyethyl cellulose and carbon nanotubesЩербаков, Н. Е., Shcherbakov, N. E. January 2023 (has links)
Разработана методика получения плёночных композиционных наноматериалов на основе гидроксиэтилцеллюлозы и углеродных нанотрубок в магнитном поле и без него. Методом поляризационной микроскопии изучена структура плёнок ГЭЦ/УНТ, полученных в магнитном поле и вне поля. Обнаружено, что полученные плёнки являются анизотропными, что связано с образованием жидкокристаллической фазы при испарении растворителя из раствора. Методом сканирующей электронной микроскопии изучена морфология плёнок ГЭЦ/УНТ, полученных в магнитном поле и вне поля. Показано, что наложение магнитного поля приводит к ориентации УНТ в пленках. Изучена равновесная сорбция паров воды плёнками ГЭЦ/УНТ. Обнаружено, что плёнки, содержащие УНТ, сорбируют меньше воды, чем плёнки без УНТ. Плёнки ГЭЦ/УНТ, полученные в магнитном поле, сорбируют меньше воды, чем плёнки, полученные вне поля. С увеличением содержания УНТ в плёнках наблюдается понижение изотерм сорбции, что может быть связано с дополнительной ориентацией УНТ в магнитном поле и уплотнением структуры плёнок. Рассчитаны разности химических потенциалов Δμ1 и разности химических потенциалов Δμ2, а также средние удельные энергии Гиббса набухания Δg для плёнок ГЭЦ/УНТ, полученных в магнитном поле и вне поля. Установлено, что разности химических потенциалов Δμ2 и энергии Гиббса взаимодействия плёнок ГЭЦ/УНТ с водой отрицательны во всей исследованной области, что говорит о самопроизвольности протекания процесса сорбции и совместимости воды с полимерной композицией. Отмечается, что введение УНТ в ГЭЦ приводит к увеличению значений энергий Гиббса и Δμ2 для плёнок ГЭЦ/УНТ с водой, что свидетельствует об ухудшении взаимодействия воды с полимерной композицией. Такое наблюдение связывается с уплотнением структуры полимера и с невозможностью УНТ сорбировать пары воды. Методом статической сорбции изучено набухание плёнок ГЭЦ/УНТ, полученных в магнитном поле. Показано, что с увеличением содержания УНТ происходит уменьшение степени набухания. Также наблюдается уменьшение степени набухания при приложении магнитного поля. На основании полученных кинетических кривых набухания рассчитаны коэффициенты диффузии. Обнаружено уменьшение коэффициентов диффузии паров воды для плёнок, полученных вне магнитного поля. Для плёнок, полученных в магнитном поле, наблюдается незначительное увеличение коэффициентов диффузии. / A technique has been developed for producing film composite nanomaterials based on hydroxyethylcellulose and carbon nanotubes in a magnetic field and without it. The structure of HEC/CNT films obtained in a magnetic field and outside the field was studied using polarization microscopy. It was found that the resulting films are anisotropic, which is associated with the formation of a liquid crystalline phase upon evaporation of the solvent from the solution.
The morphology of HEC/CNT films obtained in a magnetic field and outside the field was studied using scanning electron microscopy. It has been shown that the application of a magnetic field leads to the orientation of CNTs in films. The equilibrium sorption of water vapor by HEC/CNT films was studied. It was found that films containing CNTs absorb less water than films without CNTs. HEC/CNT films obtained in a magnetic field absorb less water than films obtained outside the field. With an increase in the CNT content in the films, a decrease in the sorption isotherms is observed, which may be due to the additional orientation of the CNTs in the magnetic field and the compaction of the film structure. The chemical potential differences Δμ1 and the chemical potential differences Δμ2, as well as the average specific Gibbs swelling energies Δg for HEC/CNT films obtained in a magnetic field and outside the field, were calculated. It was found that the differences in chemical potentials Δμ2 and the Gibbs energy of interaction between HEC/CNT films and water are negative throughout the entire studied region, which indicates the spontaneous occurrence of the sorption process and the compatibility of water with the polymer composition. It is noted that the introduction of CNTs into HEC leads to an increase in the Gibbs energies and Δμ2 for HEC/CNT films with water, which indicates a deterioration in the interaction of water with the polymer composition. It is noted that the introduction of CNTs into HEC leads to an increase in the Gibbs energies and Δμ2 for HEC/CNT films with water, which indicates a deterioration in the interaction of water with the polymer composition. This observation is associated with compaction of the polymer structure and the inability of CNTs to sorb water vapor. The swelling of HEC/CNT films obtained in a magnetic field was studied using the static sorption method. It has been shown that with increasing CNT content, the degree of swelling decreases. A decrease in the degree of swelling is also observed when a magnetic field is applied. Based on the obtained swelling kinetic curves, diffusion coefficients were calculated. A decrease in the diffusion coefficients of water vapor for fruits and vegetables outside the magnetic field was found. For films produced in a magnetic field, a significant increase in diffusion coefficients is observed.
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