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The Mn-doped ZnS nanoparticles with Td^{2}-F\overline 43~m cubic structure and an average crystalline size of about 16 nm were synthesized using the hydrothermal method at 220 ^\circC for 15 h from Zn(CH3COO)2(0.1M) , Mn(CH3COO)2(0.01M) , and Na2S2O3(0.1M) as the precursors. The appearance of characteristic photoemission bands of Mn^2+(3d^5) ions at 390, 430, 467, and 493 nm in the photoluminescence excitation spectra while monitoring the yellow-orange band at 585 nm showed that the Mn^2+(3d^10) ions substituted for Zn^2+(3d^10) ions in ZnS matrix and caused the ferromagnetism of Mn-doped ZnS nanoparticles. The dependence of photoluminescence, photoluminescence excitation spectra, and magnetization curves on Mn content and the wavelength of excitation radiation were reported. [ABSTRACT FROM AUTHOR]

The Ca0.85Pr0.15Mn1 - yRuyO3 (y = \0, 0.04, 0.08, 0.12, 0.16, and 0.20) manganate thin films were prepared by pulsed laser deposition (PLD) technique. The X-ray diffraction (XRD) analysis revealed that the samples were single-phased with orthorhombic structure. The scanning electron microscopy (SEM) images indicated that the samples were composed of homogeneous grains. The Hall-effect measurements showed that the carrier density and Hall mobility of films increased with increasing Ru-doped content. The magnetic field dependence of magnetization at various temperatures were measured by using the superconducting quantum interference device (SQUID) and showed that the increase of Ru-doping content induced the large \Delta S change in broad range of temperature. This demonstrates a possible application of these materials in cooling devices as the relative cooling power (RCP) is proportial to -(\Delta S)max \DeltaTFWHM (where \DeltaTFWHM is the full width at half-maximum of \Delta S). [ABSTRACT FROM AUTHOR]

This special section contains 38 papers selected from those ones presented at the First International Symposium on Frontiers in Materials Science (IS FMS), held in Hanoi, Vietnam, November 17?19, 2013. [ABSTRACT FROM AUTHOR]