Fast and simultaneous doping of Sr0.9-x-y-zCa0.1In2O4:(xEu3+, yTm3+, zTb3+) superstructure by ultrasonic spray pyrolysis.

In the present work, Sr0.9-x-y-zCa0.1In2O4:(xEu3+, yTm3+, zTb3+) particles were synthesized by the ultrasonic spray pyrolysis (USP) method to obtain a single-phase white phosphorus formed by six different cations in solution within the lattice (superstructure). The samples were also structurally and morphologically characterized by X-ray diffraction (XRD) techniques and by field emission scanning electron microscopy (FE-SEM). The photoluminescent behavior and the characteristics of the emitted colors were studied by the variation in the co-doping of the rare earth elements. The Sr0.9Ca0.1In2O4 sample showed a near blue color emission, but all co-doped samples showed emission in white with very close chromaticity coordinates to the standard white (x = 0.33 and y = 0.33). The Tm3+ → Tb3+ (ET1), Tm3+ → Eu3+ (ET2) and Tb3+ → Eu3+ (ET3) Energy Transfers were proposed and are considered necessary for adjusting and controlling the desired color properties.

Charge density alterations in human hair fibers: an investigation using electrostatic force microscopy.

A new method for high-resolution analyses of hair surface charge density under ambient conditions is presented in this paper. Electrostatic force microscopy (EFM) is used here to analyze changes in surface charge density in virgin hair, bleached hair, and hair treated with a cationic polymer. The atomic force microscopy technique is used concomitantly to analyze morphological changes in hair roughness and thickness. The EFM images depict exactly how the polymer is distributed on the surface of the hair fiber. The EFM's powerful analytical tools enabled us to evaluate the varying degrees of interaction between the hair fiber surface charge density and the cationic polymer. The surface charge density and the polymer's distribution in the hair fibers are presented in the light of EFM measurements.

Synthesis of SnO2 nanoribbons by a carbothermal reduction process.

This communication describes, for the first time, the growth of SnO2 nanoribbons by a controlled carbothermal reduction process. An analysis of the transmission electron microscopy image revealed that these nanoribbons have a well-defined shape, with a typical width in the range of 70-300 nm. In general, the nanostructured ribbons were more than 100 microns in length. The results reported here support the hypothesis that this ribbon-like nanostructured material grows by a vapor-solid process. This study introduces two hypotheses to explain the SnO2 nanoribbon growth process.