An attempt was made to control the surface charge of colloidal silica nanoparticles with 20 nm and 100 nm diameters. Untreated silica nanoparticles were determined to be highly negatively charged and have stable hydrodynamic sizes in a wide pH range. To change the surface to a positively charged form, various coating agents, such as amine containing molecules, multivalent metal cation, or amino...

a new hybrid nanomaterial was developed by immobilization of phosphomolybdate anions on the surface of modified magnetite nanoparticles with quaternary phosphonium cations. silica coated magnetic nanoparticles supported phosphonium cations, ph3p+-scmnps, were prepared by covalent attachment of chloropropylsilyl groups on the surface of silica coated magnetite nanoparticles and next reaction wit...

Thermal wetting can simply, selectively and reversibly join patchy particles into clusters (2D and 3D) and also colloidal crystals over the narrow temperature range of 1-2 °C. This is demonstrated with Janus particles (gold half-coated silica spheres) immersed in a binary mixture of water/2,6-lutidine, such that the relative strength of gold-gold bonding through hydrophobic interaction and sili...

In this research, mesoporous silica was applied as the host of corrosion inhibitor (molybdate). The loaded mesoporous silica was dispersed in an epoxy matrix. The composite was then coated on the mild steel plate. Results showed that the corrosion resistance of the scratched epoxy/mesoporous silica loaded by molybdate was better than the one without molybdate or neat epoxy. On the other hand, E...

Pulsed laser deposition was proved as a suitable method for hydroxyapatite (HA) coating of coaxial poly-ɛ-caprolactone/polyvinylalcohol (PCL/PVA) nanofibers. The fibrous morphology of PCL/PVA nanofibers was preserved, if the nanofiber scaffold was coated with thin layers of HA (200 nm and 400 nm). Increasing thickness of HA, however, resulted in a gradual loss of fibrous character. In addition,...

Abstract Sol–gel derived hydroxyapatite coatings on metallic implants are important to promote their osseointegration and biocompatibility. However, such generally suffer from drawbacks that limit implant longevity. In this study, the sol gel process prepare was optimized used deposit a layer Ti6Al4V. Samples were pretreated by thermal oxidation, sol–gel coating, anodization produce titanium di...

Sophisticated manipulation of surface roughness and solid surface energy are widely used to design super-hydrophobic layers. In this work, we designed highly porous silica layer with contact angle (CA) of 145°, and its robustness was promoted with thermal treatment. Wettability of coated layer is studied with CA measurement for different liquid surface tensions using diluted organi...

The disparity between in vitro silica cytotoxicity toward macrophages and their in vivo resistance to injury following inhalation of silica at physiologic concentrations is unresolved. It is probable that inhaled silica particles absorb a variety of biological substances including proteins and alveolar lining material (ALM) thus altering the in vivo response of the macrophage to these particles...

The effect of oxide coating on the activity of a copper-zinc oxide-based catalyst for methanol synthesis via the hydrogenation of carbon dioxide was investigated. A commercial catalyst was coated with various oxides by a sol-gel method. The influence of the types of promoters used in the sol-gel reaction was investigated. Temperature-programmed reduction-thermogravimetric analysis revealed that...

The transport characteristics of iron nanoparticles prepared with a green tea, polyphenol-rich solution, were investigated for two granular media, pure silica sand and sand coated with aluminium hydroxide. The GT-nZVI injection caused a sharp decrease in the effluent pH and increase in the redox potential, which is attributed to the presence of free Fe and polyphenols in the suspension, respect...