Titania was synthesized from laurylamine hydrochloride (LAHC) and Ti(SO4)2 under different acidic conditions. The effect of acidity on the structural and textural evolution of titania has been investigated by X-ray diffraction (XRD), nitrogen adsorption-desorption, transmission electron micrographs (TEM), FTIR spectroscopy and thermogravimetric analysis (TGA). With increasing the pH value in the initial mixture, the obtained samples transformed from nanoparticles with intra-particle mesostructures (pH 0.6 and 2.0) to nanoparticles with nonporous structure (pH 3.7), and finally to worm-like porous materials with inter-particle mesostructures (pH 4.2)resulted from the aggregates of nanoparticles. The obtained mesoporous nanoparticles (pH 0.6 and 2.0) have mean diameter of ca. 25 nm, and the pore size distributions are bimodal with fine intra-particle pores and larger inter-particle pores. The intra-particle mesostructure not only retard the growth of nanocrystallites, but also prevent phase transition of anatase to rutile at high temperature. The BET surface area of the TiO2 calcined at 300 C decreased from 212 to 74 m2/g with pH increasing from 0.6 to 4.2.

Researchers have been playing with advanced synthetic materials known as polymers and composites for several de-cades now. In the 1980s, a buzz word for materials scientists was "intelligent" or "smart" materials. In the mid-1990s the new buzzing became the creation nanostructured materials.[1] Nanometer is one billionth part of a meter. Literally "nano" represents 0.000000001 or 10 9. Defined broadly, the term "nanostructured" is used to describe materials characterized by structural features of less than 100nm in average size. The average size of an atom is of the order of 1 to 2 A in radius. 1 nanometer comprises 10 A, and hence in one nanometer, there may be 3-5 atoms, depending on the atomic radii. Man-ufactured products are made from atoms and the properties of such products depend on their atomic structure. If the car-bon atoms in coal are rearranged, diamonds can be made. Seashells, as we all know, are extraordinary tough and this crack and shatter resistant property are attributed by an ex-quisite nanostructure.[2] Nanotech is the most significant emerging materials technology for the next century. Research in nanostructured materials is motivated by the belief that ability to control the nanostructure of these materials can re-sult in enhanced properties at the macroscale viz. increased hardness, ductility, catalytic enhancement, selective absorp-tion, higher efficiency optical or electrical behavior. Experi-ments in the field of nanostructured materials have produced very significant and interesting results. The science of ceramic nanoparticles is no exception with much success in areas in-cluding synthesis, surface science, texturology, catalysis etc.[3] Chemistry of Nanoparticles Within the intermediate region of 2-10nm, neither quan-tum chemistry nor classical laws of physics hold. For example--in spherical nanoparticles with a size of 3nm, 50% of the atoms or ions are on the surface, allowing the possibility of manipulation of bulk properties by surface effects.[3] As the particles become smaller in size they may take on different morphologies that may alter surface chemistry and adsorp-tion properties in addition to increasing the surface area. These nanoparticles also possess a much greater number of defect sites per unit surface area, which are believed to be responsible for the observed chemistry. As the size of a parti-cle decreases, the percentage of atoms residing on the surface increases and of course these surface atoms are expected to be more reactive than their bulk counterparts as a result of coordinative unsaturation. Because of this and because of the fact that surface-to-volume ratio is large, it is not unusual to see unique chemical, physical or adsorptive properties and characteristics for nanoparticles.

Eu2 +,Dy3 + co-doped strontium aluminate (SrAl2O4) phosphor nanoparticles with high brightness and long afterglow were prepared by glycine-nitrate solution combustion synthesis at 500℃, followed by heating the resultant combustion ash at 1100℃ in a weak reductive atmosphere of active carbon. The average particle size of the SrAl2O4:Eu,Dy phosphor nanoparticles ranges from 15 to 45nm as indicated by transmission electron microscopy (TEM). The broad-band UV-excited luminescence of the SrAl2O4:Eu,Dy phosphor nanoparticles was observed at kmax=513nm due to transitions from the 4f65d1 to the 4f7 configuration of the Eu2+ion. The results indicated that the main peaks in the emission and excitation spectrum of phosphor nanoparticles shifted to the short wavelength compared with the phosphor obtained by the solid-state reaction synthesis method. The decay speed of the afterglow for phosphor nanoparticles was faster than that obtained by the solid-state reaction method.

A method for the determination of trace amounts of La, Y and Eu, based on the formation of volatile chelates between rare earth elements and 1-phenyl-3-methyl-4-benzoyl-pyrazolone [5] (PMBP) in a graphite furnace, is described. PMBP was used as a chemical modifier for the volatilization of La, Y and Eu from the electrothermal vaporizer into the ICP. The factors affecting the chelating reaction between La, Y and Eu and PMBP were studied in detail, and the vaporization behavior of the chelates formed in the graphite furnace was also investigated. It was found that the presence of an excess of PMBP was necessary to prevent the thermal decomposition of the chelates during the volatilization and transportation processes. Under the optimized conditions, the limits of detection for La, Y and Eu are 8.0, 1.0 and 0.9 ng ml-1, respectively, and the relative standard deviations range from 3.3% (La) to 4.0% (Y). The linear ranges of the calibration graphs span three orders of magnitude. The method was applied to the analysis of an environmental reference material and the results obtained were in good agreement with the reference values.

The vaporization behavior of silicon and three refractory trace elements (Al, Ti and Y) were studied in the presence and absence of a PTFE emulsion as fluorinating reagent and applying an electrothermal ICP-AES coupled system.It was found that during a 60 s ashing step at 700℃ about 90% of 100mg of Si3N4 can be decomposed and evaporated without considerable losses of the trace elements investigated. Calibration could be carried out by the standard addition method and the calibration curve method applying spiked slurries and aqueous standard solutions with peak height intensity measurements, respectively. The detection limits varied from 0.11 mg g−1 (Al) to 0.09mg g−1 (Ti) with RSD 1.9-4.2%.