Preliminary positron lifetime results on free volumes in cyclodextrins

M. F Ferreira Marques, A. M G Moreira Da Silva, P. M. Gordo, Z. Kajcsos

Research output: Chapter in Book/Report/Conference proceedingConference contribution

4 Citations (Scopus)

Abstract

Positron annihilation lifetime spectroscopy was used to study the free-volume parameters in various pure α-, β- and γ-cyclodextrins samples and, in the case of β-cyclodextrin, with inclusion of S-carvone and thymoquinone. The results clearly indicate the presence of long lifetime components related to Ps-formation. The data show that the addition of S-carvone to β-cyclodextrin results in a decrease of o-Ps lifetime that we ascribe to a reduction of free volume holes from 81.8 to 63.7 Å3. The long lifetime component disappears when thymoquinone is added to β-cyclodextrin, indicating this substance acts as an o-Ps quencher. For all samples studied, a decrease in the long lifetime component values was observed with increasing source in situ time, a result that might be attributed to the irradiation of the sample by the 22Na positron source.

Original languageEnglish
Title of host publicationMaterials Science Forum
Pages99-102
Number of pages4
Volume666
DOIs
Publication statusPublished - 2011
Event39th Polish Seminar on Positron Annihilation, PSPA-10 - Kazimierz Dolny, Poland
Duration: Jun 20 2010Jun 25 2010

Publication series

NameMaterials Science Forum
Volume666
ISSN (Print)02555476

Other

Other39th Polish Seminar on Positron Annihilation, PSPA-10
CountryPoland
CityKazimierz Dolny
Period6/20/106/25/10

Fingerprint

Cyclodextrins
Free volume
Positrons
positrons
life (durability)
Positron annihilation
positron annihilation
Irradiation
Spectroscopy
inclusions
irradiation
spectroscopy
thymoquinone
carvone

Keywords

  • Cyclodextrins
  • Free-volume
  • Inclusions complex
  • Positron lifetime

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanical Engineering
  • Mechanics of Materials

Cite this

Marques, M. F. F., Moreira Da Silva, A. M. G., Gordo, P. M., & Kajcsos, Z. (2011). Preliminary positron lifetime results on free volumes in cyclodextrins. In Materials Science Forum (Vol. 666, pp. 99-102). (Materials Science Forum; Vol. 666). https://doi.org/10.4028/www.scientific.net/MSF.666.99

Preliminary positron lifetime results on free volumes in cyclodextrins. / Marques, M. F Ferreira; Moreira Da Silva, A. M G; Gordo, P. M.; Kajcsos, Z.

Materials Science Forum. Vol. 666 2011. p. 99-102 (Materials Science Forum; Vol. 666).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Marques, MFF, Moreira Da Silva, AMG, Gordo, PM & Kajcsos, Z 2011, Preliminary positron lifetime results on free volumes in cyclodextrins. in Materials Science Forum. vol. 666, Materials Science Forum, vol. 666, pp. 99-102, 39th Polish Seminar on Positron Annihilation, PSPA-10, Kazimierz Dolny, Poland, 6/20/10. https://doi.org/10.4028/www.scientific.net/MSF.666.99
Marques MFF, Moreira Da Silva AMG, Gordo PM, Kajcsos Z. Preliminary positron lifetime results on free volumes in cyclodextrins. In Materials Science Forum. Vol. 666. 2011. p. 99-102. (Materials Science Forum). https://doi.org/10.4028/www.scientific.net/MSF.666.99
Marques, M. F Ferreira ; Moreira Da Silva, A. M G ; Gordo, P. M. ; Kajcsos, Z. / Preliminary positron lifetime results on free volumes in cyclodextrins. Materials Science Forum. Vol. 666 2011. pp. 99-102 (Materials Science Forum).
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