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Abstract  

Thermogravimetric analysis was applied to the characterization of the porosity of silica gels. Results from thermogravimetric method are compared with those obtained from the nitrogen method. The consistency of the parameters characterizing the porous structure of silica gels derived from the data of various methods is satisfactory.

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Abstract  

Effect of the presence of I-4 Me-Ph ionene in the supramolecular template (cetyltrimethylammonium bromide) on formation of porous structure of silicas has been studied. As-synthesized nanocomposites were characterized by using thermal analysis. Nitrogen adsorption–desorption measurements, X-ray diffraction and scanning electronic microscopy were applied to determine adsorption-structural characteristics and morphology of particles of the mesoporous templated silicas prepared in basic media.

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Abstract  

Supramolecular structures of lecithin occurred to be the template in the synthesis of mesoporous aluminosilicates; using of various combinations of lecithin and cetyltrimethyl-ammonium bromide or octadecylamine as templating agents allowed to obtain mesoporous substances with pores up to 100 , as well as biporous materials in aluminosilicate system. In the presence of glucose oxidase and cetyltrimethyl-ammonium bromide combinations aluminosilicate substances with complex porous structure were shown to be formed (pore size distributions exhibited 3 peaks, corresponding 3 effective size of mesopores in the 30–100 range). The investigation of sorption of glucose oxidase on obtained aluminosilicate mesoporous substances was carried out, the results obtained allowus to consider such materials as prospect for creation high capable and selective sorbents for biomolecules sorption, as well as active elements of chemical and biosensors.

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Preparation of microspherical granules from aerosilogels

The way of spray drying in overheated water steam

Journal of Thermal Analysis and Calorimetry
Authors: Jadwiga Skubiszewska-Zięba and V. Sydorchuk

Abstract  

The influence of the conditions of aerosil dispersion spray drying process in the medium of overheated water steam on the formation of microspheric granules and their porous structure was studied. Water and ammonium solutions as aerosil particles dispersing agents and water steam and air as heat carriers were used. It was stated that the effects of spray drying depend on the kind of dispersing medium and on the conditions of atmosphere and temperature at which drying and forming of aerosilogel granules takes place.

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Journal of Thermal Analysis and Calorimetry
Authors: V. Sydorchuk, W. Janusz, S. Khalameida, E. Skwarek, J. Skubiszewska-Zięba, R. Leboda, and V. Zazhigalov

measurements. The parameters of porous structure (specific surface area S , sorption pore volume V s , micropores volume V mi , mesopores volume V me ) were determined from the isotherms of low-temperature nitrogen adsorption obtained by means of

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Abstract  

The aim of the present study was the pore structure characterization of porous glass derived from a leachable precursor. Two independent techniques were applied on this purpose. The interpretation of the results obtained by these techniques, i.e. thermoporometry and nitrogen porosimetry was indicative for their supplementary character in what concerns the calculation of pore size distributions. The experimental work described in this study gives an example for the monitoring of the compositional evolution of phase separating compact-glass precursors of porous glasses.

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Journal of Thermal Analysis and Calorimetry
Authors: V. Sydorchuk, S. Khalameida, J. Skubiszewska-Zięba, and R. Leboda

diameter of 10 mm and total weight of 40.5 g and the vessel of silicon nitride volume of 80 mL were used. Physical–chemical characterization The parameters of porous structure were determined from isotherms of

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Szychowski , D Żmijewski , T et al. 2000 Computer program for evaluation of parameters of porous structure of solids Forum Chemiczne 2000 Warsaw . 7 Bhattacharya

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. Such materials are characterized by high specific surface area and well developed porous structure with ordered framework and narrow pore size distribution. The structure of mesoporous materials allows using them as host materials, catalyst for

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heterogeneous porous structure, micro pores with the smallest diameters are filled up at low pressures of the adsorbate. With increasing adsorbate gas pressure pores of larger diameter are filled up and the multi-layer adsorption takes place. The specific

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