Biomimetic formation of silica from polyamines such as poly(ethylene imine) (PEI), inspired by the proteins found in diatoms and sponges, has been actively investigated recently as a potential route to silica formation compared to the conventional sol–gel process. We report silica formation onto nanofibers of PEI blended with poly(vinyl pyrrolidone) (PVP) obtained via electrospinning of their 5...

This paper describes an improved procedure for the efficient and facile synthesis of 4-aryl substituted 3, 4-dihydropyrimidinones under mild reaction conditions with excellent yields using inexpensive silica chloride under solvent free conditions.

Cationic surfactant-mediated systems containing different concentrations of cetylpyridinium chloride have been used as mobile phases in thin-layer chromatographic separation of metal cations on silica layers. The effect of surfactant concentrations below and above the critical micelle concentration (CMC) on the retention behaviour of metal ions was examined. The best TLC system for rapid mutual...

This paper was conducted to study the behavior of lightweight concrete, incorporating local lightweight aggregate (LWA), in terms of chloride ion permeability at different ages. The effect of lightweight fine aggregate replacement by normal weight sand (0, 25, 50 and 75% by volume) was investigated. Constant level of silica fume content (10% by weight of cement) as an addition was also consider...

Tungsten oxide (WO3) nanostructure were synthesized by a facile hydrothermal method at 150° C using tungstate dehydrates (Na2WO4.2H2O) as the precursor. Without any additive, scanning electron microscopy revealed a rhombus shaped WO3 nanostructures while with the addition of sodium chloride, the morphology changes to nano-dagger bundles that formed flower-like structure. Furthermore, the size o...

Silica-titania monoliths with micrometer-scale macroporous and nanometer-scale mesoporous structure and high titania contents are prepared by sol-gel process and phase separation. Titanium alkoxide precursor was not effective in the preparation of high titania content composites because of strong decrease in phase separation tendency. Bimodal porous gels with high titania content were obtained ...

This paper introduces and proves new concept of salt dissolving in water as very tiny solid sodium chloride particles of nanovolumes, from this point of view salt water can be desalinated by collision with special surface characterized by smoothness upon nano level, high rigidity, high hardness under appropriate conditions of water launching in the form of thin laminar flow under suitable speed...

knoevenagel condensation between barbituric acid and aldehyde was investigated in the presence of sulfonic acid functionalized nanoporous silica (sba-pr-so3h) and resulted in the formation of arylidene and bis-arylidene barbiturates. excellent yields and short reaction times are related to the high efficiency of sba-pr-so3h that the reactions take place easily in its nano-pores. sba-pr-so3h as ...

This paper describes the synthesis and chromatographic and morphologic characterization of two monolithic silica nano-columns (50 µm i.d.) prepared by sol-gel processes, using hydrophilic interaction (HILIC) mode separations to evaluate their performance. Two types of monoliths were prepared by varying the precursors (tetraethoxysilane or a tetraethoxysilane-methyltrimethoxysilane mixture) and ...

cobalt is an essential co-factor in red blood cell production and function and its deficiency may produce clinical signs in sheep. thus, present study was designed to evaluate the effect of cobalt nano-particles on serum biochemical factors and histopathological changes in liver and kidnies of lambs. study was carried out in 3 groups of lambs (4 lambs per group). one group of lambs was kept as ...