Silica scaling is probably the principal factor limiting the extraction of energy from high temperature geothermal systems. Silica exists in a number of polymorphs from quartz through to opal A (or amorphous silica). The thermodynamics of the solubility of quartz and amorphous silica with variations in temperature, salt content, pH and pressure are discussed. However, in silica saturated geothe...

incorporation of copper species into silica matrix was performed by the sol-gel method. copper ions and copper particles were doped using two different copper sources; cu(no3)2.3h2o and copper particles chemically synthesized.the particles of copper metallic, cuprous and cupric oxide were prepared and the synthesis and characterizations of copper species were compared together. on the other han...

Carbon-silica composites with mesoporous structures were synthesized from low-cost materials by conventional heating. The carbon source used was vinasse, a by-product of ethanol production molasses, while Na2SiO3 and K2SiO3 utilized as low cost abundantly available silica sources alternatives to tetraethyl orthosilicate (TEOS). simple preparation method adopted follows: vinasse dehydrated 50% H...

Core-polystyrene/shell-silica nanocomposite particles are synthesized by simple soap-free emulsion polymerization employing positively charged silica sol. The polymerization is initiated with conventional anionic KPS. It is found that the silica sol should be added after the initiation and nucleation of the soap-free emulsion polymerization in order to obtain colloidally stable composite partic...

occupational exposure to heavy metals, organic solvents and silica is associated with a variety of renal manifestations. improved understanding of occupational renal disease provides insight into environmental renal disease, improving knowledge of disease pathogenesis. silica (sio 2 ) is an abundant mineral found in sand, rock, and soil. workers exposed to silica include sandblasters, miners, q...

Lanthanide ions are promising for the labeling of silica nanoparticles with a specific luminescent fingerprint due to their sharp line emission at characteristic wavelengths. With the increasing use of silica nanoparticles in consumer products, it is important to label silica nanoparticles in order to trace the biodistribution, both in the environment and living organisms.In this work, we synth...

We successfully synthesized two different structures, silica nanospheres and porous polymer membranes, via nanophase separation, based on a sol-gel process. Silica sol, which was in situ polymerized from tetraorthosilicate, was used as a precursor. Subsequently, it was mixed with a polymer that was used as a matrix component. It was observed that nanophase separation occurred after the mixing o...

the aim of this study was to investigate the influence of various treatments with filter-aids on pomegranate juice quality. the pomegranate used in this study was malas variety. different treatments in cold clarification method attempted were pectolitic enzyme, pectolitic enzyme-gelatin-bentonit, pectolitic enzyme-gelatin-silica sol, pectolitic enzyme-gelatin-bentonit-silica sol, gelatin-benton...

Diatoms are eukaryotic microalgae that produce species-specifically structured cell walls made of SiO(2) (silica). Formation of the intricate silica structures of diatoms is regarded as a paradigm for biomolecule-controlled self-assembly of three-dimensional, nano- to microscale-patterned inorganic materials. Silica formation involves long-chain polyamines and phosphoproteins (silaffins and sil...

The interaction of DNA with crystalline silica in buffered aqueous solutions at physiologic pH has been investigated by Fourier-transform infrared spectroscopy (FT-IR). In aqueous buffer, significant changes occur in the spectra of DNA and silica upon coincubation, suggesting that a DNA-silica complex forms as silica interacts with DNA. As compared to the spectrum of silica alone, the changes i...