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Highly dispersed nanometer-sized a-Fe 2 O 3 (hematite) and c-Fe 2 O 3 (maghemite) iron oxide particles were synthesized by the combustion method. Ferric nitrate was used as a precursor. Xray diffractometer study revealed the phase purity of aand c-Fe 2 O 3 . Both the products were characterized using field emission scanning electron microscope and transmission electron microscope for particle size and morphology. Necked structure particle morphology was observed for the first time in both the iron oxides. The particle size was observed in the range of 25-55 nm. Photodecomposition of H 2 S for hydrogen generation was performed using aand c-Fe 2 O 3 . Good photocatalytic activity was obtained using aand c-Fe 2 O 3 as photocatalysts under visible light irradiation. P. Gouma-contributing editor

The simple, template-free, low-temperature, large-scale synthesis of nanostructured CdS with the hexagonal wurtzite phase from bulk cadmium oxide under solid-phase conditions is demonstrated for the first time. The novel approach involves the homogenization of cadmium oxide (CdO) and thiourea in various stoichiometric ratios at moderate temperature. Among the different molar ratios of CdO and thiourea studied, the CdO/NH(2) CSNH(2) molar ratio of 1:2 is found to be the best to obtain highly pure CdS. The obtained CdS nanostructures exhibit excellent cubic morphology and high specific surface area with a particle size in the range of 5-7 nm. The bandgap of the nanostructured CdS is in the range of 2.42 to 2.46 eV due to its nanocrystalline nature. In photoluminescence studies, emission is observed at 520.34 and 536.42 nm, which is characteristic of the greenish-yellow region of the visible spectrum. Considering the bandgap of the CdS is within the visible region, the photocatalytic activity for H(2) generation and organic dye degradation are performed under visible-light irradiation. The maximum H(2) evolution of 2945 μmol h(-1) is obtained using nanostructured CdS prepared in the 1:2 ratio, which is three times higher than that of bulk CdS (1010 μmol h(-1) ). CdS synthesized using the 1:2 molar ratio shows maximum methylene blue degradation (87.5%) over a period of 60 min, which is approximately four times higher than that of bulk CdS (22%). This amazing performance of the material is due to its nanocrystalline nature and the high surface area of the CdS. The proposed simple methodology is believed to be a significant breakthrough in the field of nanotechnology, and the method can be further generalized as a rational preparation scheme for the large-scale synthesis of various other nanostructured metal sulfides.

Polymorphous low-grade adenocarcinoma (PLGA) is difficult to diagnose due to its indolent clinical presentation and due to its morphological diversity that includes several microscopic patterns. Distinguishing it from high-grade tumors of salivary gland is important, as the management and prognosis of this tumor differ. We report a considerably rare case of PLGA in retromolar area highlighting various diagnostic challenges caused by the overlap of clinical and microscopic features between PLGA and other salivary gland neoplasms and discuss current management strategies.

Spherically shaped plasmonic Au nanoparticles (NPs) of size 10 nm (±4 nm) have been decorated on TiO2 NPs for the synthesis of Au@TiO2 composites via an aqueous sol–gel method.