Mn-doped PbS nanocrystals (NCs) in an oxide glass matrix have been synthesized by the fusion method. Two kinds of Mn2+ sites, located inside and on the surface of NCs, are observed by electron paramagnetic resonance (EPR) spectroscopy in the X band and at room temperature. The proportion of their contribution to the hyperfine structure in the EPR spectrum depends strongly on thermal annealing time. The authors illustrate how thermal annealing process manifests itself in engineering the magnetic properties of NCs.

Two natural zircon samples A and B from Minas Gerais State, Brazil were investigated. Large amounts of Fe, Y, Ce, U and Th were detected as impurities in two samples. TL peaks at 145, 190, 240 and 290 o C in both samples were found, with sublinear growth. The emission spectra of TL light present two bands, one at 480 nm and the other one at 580 nm indicating that there are two recombination centers. The heat treatment at 500, 600, 700, 800 and 900 o C before irradiation produces increases in TL sensitivity with temperature. [2] investigated then the TL dosimetric properties of natural zircon from Cambodia, after irradiating it with UV-,X-, -, and ß-rays. TL peaks at 325-350, 385-390, 540, and 595-625 K were detected. The third peak emits 480 and 580 nm light, the fourth peaks, 545 nm light. The 480 and 580 nm bands are due to Dy 3+ and the 545 nm band to Tb

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