Rearrangement of hexadecane molecules confined in the nanopores of a controlled pore glass using positron annihilation and differential scanning calorimetry

Autor:	Igor Maťko, Eva Macová, Ondrej Šauša, Jozef Krištiak, Emília Illeková
Rok vydání:	2013
Předmět:	Chemistry Kinetics Analytical chemistry Hexadecane Condensed Matter Physics Isothermal process law.invention Nanopore chemistry.chemical_compound Differential scanning calorimetry law Molecule Physical and Theoretical Chemistry Crystallization Cetane number
Zdroj:	Journal of Thermal Analysis and Calorimetry. 113:1187-1196
ISSN:	1572-8943 1388-6150
DOI:	10.1007/s10973-013-3030-6
Popis:	The solidification/melting of cetane confined in nine silica glasses with specific controlled pores (CPG) with different pore sizes (r p ranging from 3.7–72 nm) has been studied. Samples with variable coefficient of filling of cetane were prepared and analyzed. Combining the indication of the evolving solidification heats (via differential scanning calorimetry, DSC) with the lifetime spectra of positron annihilation, the mechanism of filling of cetane molecules in the pores of the hosting silica glass matrices has been searched. Three independent solidification effects—three independent DSC peaks—were observed in each measuring cycle, namely one crystallization exotherm Rb of the bulk-cetane (if present) and two crystallization sub-peaks Rc1 and Rc2 of the confined cetane in the case of continuous cooling. The temperatures of both Rc1 and Rc2 effects decrease on decreasing the r p of the CPG matrix. The mutual relation between Rc1 and Rc2 has been analyzed. The kinetics of all three steps of the solidification in the continuous-cooling as well as isothermal regimes have been specified.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::7f30e4b6d019154c60a7eff2fe7d9f5f https://doi.org/10.1007/s10973-013-3030-6 Zobrazit plný text záznamu Plný text ve formátu PDF