Positron annihilation in precious and common opals

• Autorzy: Chojcan J. , Sachanbiński M. , Idczak R. , Konieczny R.
• Konferencja: Proceedings of the 40th Polish Seminar on Positron Annihilation PSPA'2012, 13-14 June 2012, Kazimierz Dolny, Poland
• Języki publikacji: EN

Abstrakty

EN

The nano-porosity structure of several non-crystalline opal samples of different origin was investigated with positronium atoms. The obtained data show that the structure depends on both the kind of opal (precious, common or hyalite) as well as the place of its creation (sedimentary or volcanic rocks). The sizes of the pores "seen" by positronium atoms are relatively small, not greater than about 1 nm for all studied samples which may suggest that the pores are located inside the silica matter from which the samples are made. Moreover, the pores detected in the "sedimentary" precious opals are smaller and have less diverse sizes than those found in 'sedimentary" common opals and "volcanic' precious opals.

Słowa kluczowe

EN

opal-A; porosity; positron annihilation

• Wydawca: Institute of Nuclear Chemistry and Technology
• Czasopismo: Nukleonika
• Rocznik: 2013
• Tom: Vol. 58, No. 1
• Strony: 225--228
• Opis fizyczny: BIbliogr. 9 poz., rys.

Twórcy

autor

Chojcan J.

autor

Sachanbiński M.

autor

Idczak R.

autor

Konieczny R.

• University of Wrocław, Institute of Experimental Physics, 9 M. Borna Sq., 50-204 Wrocław, Poland, Tel.: [phone], Fax: [phone],

Bibliografia

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