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dc.creatorPetrović, R.
dc.creatorJanaćković, Đorđe
dc.creatorZec, Slavica
dc.creatorDrmanić, Saša
dc.creatorKostić-Gvozdenović, Ljiljana
dc.date.accessioned2021-03-10T10:07:01Z
dc.date.available2021-03-10T10:07:01Z
dc.date.issued2003
dc.identifier.issn0928-0707
dc.identifier.urihttp://TechnoRep.tmf.bg.ac.rs/handle/123456789/532
dc.description.abstractAlkoxy-derived cordierite gels were synthesized from tetraethylorthosilicate (TEOS), aluminum isopropoxide (Al(OPri)(3)), and magnesium ethoxide (Mg(OEt)(2)). TEOS was partially hydrolyzed at molar ratios H2O/TEOS=1.2, in the presence of hydrochloric acid as a catalyst, HCl/TEOS=0.1. Aluminum and magnesium alkoxides were added successively or as a double alkoxide. Phase transformations occurring in the gel were studied by differential thermal analysis, x-ray diffractometry, and Fourier-transform infrared spectroscopy. In all cases, mu-cordierite crystallized at similar temperatures (950-1000degreesC) with small amounts of spinel, which confirms dominant influence of the optimal conditions for partial hydrolysis of TEOS on the gels homogeneity. The transformation of mu- into alpha-cordierite began at about 1100degreesC. Broadening of diffraction peaks and appearance of new bands in the FT IR spectra confirmed the transformation of alpha- into modulated beta-cordierite at temperatures above 1300degreesC. Differential thermal analysis under nonisothermal conditions also proved homogeneous nucleation with constant rate and three-dimensional crystallite growth during mu-cordierite crystallization. The overall activation energy of the crystallization of mu-cordierite is 580+/-81 kJ/mol.en
dc.publisherSpringer, New York
dc.rightsrestrictedAccess
dc.sourceJournal of Sol-Gel Science and Technology
dc.subjectcordieriteen
dc.subjectsol-gel processen
dc.subjectphase transformationsen
dc.subjectkinetics of crystallizationen
dc.titleCrystallization behavior of alkoxy-derived cordierite gelsen
dc.typearticle
dc.rights.licenseARR
dc.citation.epage118
dc.citation.issue1
dc.citation.other28(1): 111-118
dc.citation.rankaM21
dc.citation.spage111
dc.citation.volume28
dc.identifier.doi10.1023/A:1025649406466
dc.identifier.scopus2-s2.0-0141990994
dc.identifier.wos000185229200015
dc.type.versionpublishedVersion


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