Synthesis of multi-walled carbon nanotubes by spray-pyrolysis using a new iron organometallic complex as catalytic agent.

An organometallic catalytic agent ([(Hexyl)4N]3FeCl3Br3) has been synthesized through the reaction of tetrahexylammonium bromide ((Hexyl)4NBr) and iron chloride (FeCl3) aqueous solutions. Multi-walled carbon nanotubes (MWCNTs) were obtained by spray pyrolysis of toluene (carbon source) using the new organometallic compound as catalyst. The synthesized catalytic agent was characterized by ultraviolet-visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR), and thermal analysis (TA) techniques.

Simplified route to multi-walled carbon nanotube synthesis by aerosol assisted chemical vapor deposition.

Uniform multi-walled carbon nanotubes (MWCNTs) were obtained decomposing toluene inside of fused silica tubing previously covered with Co oxide thin film. The two-step process, ruled successively in the same aerosol assisted chemical vapor deposition (AACVD) set up, constitutes a simplified route to the synthesis of MWCNTs. First, Co oxide thin film was deposited inside of fused silica tubing at 723 K, using a precursor solution of Co acetate in absolute methanol.

Synthesis and characterization of porous Mo-W oxide nanostructures.

The present study reports the synthesis method, microstructure characterization, and thermal stability of nanostructured porous mixed oxide (MoO3-WO3) at 550 and 900 degrees C of annealing. The material was synthesized using a hydrothermal method. The precursor was prepared by aqueous solution using ammonium heptamolibdate and ammonium metatungstate, with an atomic ratio of Mo/W = 1.

Optimization of the synthesis of alpha-MoO3 nanoribbons and hydrodesulfurization (HDS) catalyst test.

An optimized process for synthesis of alpha-MoO3 nanoribbons characterized by uniform morphology and composition was carried out. The optimized process turned out to be the aging of a precursor of an aqueous solution of ammonium heptamolybdate for a week under constant stirring at 333 K; followed by hydrothermal treatment for 36 h up to 48 h at 473 K. The dimensions of the nanoribbons were between 5 and 10 microm in length and a width between 100 and 600 nm.

[Prevalence of iodine deficiency and related factors in 4 year-old schoolchildren].

Background And Objective: Iodine deficiency in early years of life can cause important disorders in body growth and development. The aim of this study was to determine the prevalence of iodine deficiency in 4 year-old schoolchildren from the town of Mataró (Barcelona, Spain) and to know the factors associated with this nutritional deficiency.

Patients And Method: A population-based cross-sectional study was designed, which included all 4 year-old schoolchildren of this town.