Positron annihilation lifetime spectroscopy of nano/macroporous bioactive glasses

被引：9

作者：

Golovchak, Roman ^{[1
]}

Wang, Shaojie ^{[1
]}

Jain, Himanshu ^{[1
]}

Ingram, Adam ^{[2
]}

机构：

[1] Lehigh Univ, Dept Mat Sci & Engn, Bethlehem, PA 18015 USA

[2] Opole Univ Technol, Dept Phys, PL-45370 Opole, Poland

来源：

JOURNAL OF MATERIALS RESEARCH | 2012年 / 27卷 / 19期

基金：

美国国家科学基金会;

关键词：

SOL-GEL; SILICA-GEL; PHASE-SEPARATION; PORE STRUCTURE; SCAFFOLDS; TEMPERATURE; POROSITY; FOAMS;

D O I：

10.1557/jmr.2012.252

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Positron annihilation lifetime measurements are performed for sol-gel-derived 70 mol% SiO2-30 mol% CaO bioactive glass. Strong positronium formation processes are shown to be an inherent feature for these kinds of materials. Observed orthopositronium (o-Ps) lifetimes show a three-modal distribution with lifetime values weighed at similar to 2, similar to 18, and similar to 70 ns. The exposure of the investigated sol-gel-derived bioactive glasses to water vapor significantly modifies o-Ps lifetime distribution due to the penetration of water molecules into the nanopores, indicating high ratio of their interconnectivity. Classic Tao-Eldrup equation is used to relate the o-Ps lifetimes with the size of nanopores, whose distribution is verified by nitrogen adsorption porosimetry.

引用

页码：2561 / 2567

页数：7

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