The size and numerical concentration of free volume of HDPE/CB composites were estimated by means of positron annihilation lifetime measurement, in which annihilations of positron and positronium were assessed.

We have investigated the electrically active deep level defects in n-type 6H silicon carbide through the use of a series of complimentary spectroscopic techniques such as deep level transient spectroscopy, positron annihilation spectroscopy and photoluminescence.

Long afterglow SrAl2O4:Eu,Dy phosphor was prepared by the traditional ceramic synthesis method, and investigated its luminescent mechanism and properties by the thermolumi-nescence and positron annihilation method.

The usual commercial softwares of γ-ray spectrum analysis could not accurately fit the multiplet region with positron annihilation peak,because the positron annihilation peak is greatly different from other peaks.

The results indicated that the dye sensitized TiO_2 extended its absorption range into the visible-light region and occured the phenomenon of the electron annihilation by organic dye sensitized TiO_2.

The sulfonated polyetherketone with cardo group(SPEK-C) films made by different sulfonation degrees and solvent evaporation shows the different microstructure by positron annihilation lifetime spectroscopy(PALS) and atomic force microscopy(AFM).