as we know sol-gel is one of the most important techniques for thin film preparation. in this paper, high transmission silica thin films have been prepared by dip-coating process from a new silicon-alkoxide solution. the prepared sol was stable for 45 days which is very important to characterize the coating process. the optical properties as a function of aging time, withdrawal rate, and heat t...

Fabrication of monodisperse pure silica and core-shell nanospheres (Fe2O3@SiO2 and Fe2O3/QD@SiO2) was done in straight forward one-pot method combining sol-gel chemistry and supercritical fluids. For the core-shell materials, preformed nanoparticles stabilized in hexane were dispersed in a sol containing a silicon alkoxide, water and acetone as the solvent. The precursor solution was introduced...

2,2'-Bipyridine-ligated copper complexes, in combination with TEMPO (2,2,6,6-tetramethylpiperidine-N-oxyl), are highly effective catalysts for aerobic alcohol oxidation. Considerable uncertainty and debate exist over the mechanism of alcohol oxidation mediated by Cu(II) and TEMPO. Here, we report experimental and density functional theory (DFT) computational studies that distinguish among numer...

We study the droplet-based synthesis of fluorescent silica nanoparticles (50-350 nm size) in a microfluidic chip. Fluorescein-isothiocyanate (FITC) dye is first chemically linked to aminopropyl triethoxysilane (APTES) in ethanol and this reaction product is subsequently mixed with tetraethyl orthosilicate (TEOS) to yield a fluorescent silicon alkoxide precursor solution. The latter reacts with ...

A crystallized SrTiO3 (STO) nanocoating on a primary SiO2 nanoparticle was produced by metal alkoxide processing with chemical modification. The coated layer surface morphology and the coating amount were controlled molecular design of STO precursor solution. When using partially hydrolyzed solution (a polymerized solution), an approximately 10-nm-thick homogeneous obtained core particle. From ...

The synthesis and characterization of two new tetronic acid zinc (II) complexes of the empirical formulae [Zn(L-H)(2)(H(2)O)(2)] (1) and [Zn(L-H)(2)(H(2)O)(MeOH)]H(2)O (2) found within the same crystal are reported. The zinc ions bind through alkoxide and carbonyl groups of the ligand 3-methoxycarbonyl-5-phenyl tetronic acid (LH) as indicated by (1)H NMR and X-ray crystallographic studies. Thes...

Reaction of 2-methylcyclohexanone with lithium hexamethyldisilazide (LiHMDS, TMS(2)NLi) displays highly solvent-dependent chemoselectivity. LiHMDS in THF/toluene effect enolization. Rate studies using in situ IR spectroscopy are consistent with a THF concentration-dependent monomer-based pathway. LiHMDS in pyrrolidine/toluene affords exclusively 1,2-addition of the pyrrolidine fragment to form ...

Three ferrous/ferric complexes of a N6 hexadentate ligand, N,N,N',N'-tetrakis(2-benzimidazolyl-methyl)ortho-diamine-trans-cyclohexane (ctb), [Fe(II)(ctb)](ClO(4))(2).EtOH (), [Fe(III)(OEt)(Hctb)](ClO(4))(3).EtOH (), and [Fe(III)(OMe)(Hctb)](ClO(4))(3).3MeOH.4.5H(2)O (), were synthesized and characterized as models of lipoxygenase. The lipoxygenase activities of the complexes were checked and th...