The hydrothermal stability of molecular sieve silica (MSS) membranes is an area of increasing research interest, in particular for applications such as membrane reactors and membrane gas separation of process streams containing hot steam. In these applications, gas streams are likely to contain water vapor, which reacts with the hydrophilic sites in the silica thin films resulting in chemical a...

Compared with pure silica-based or organic-polymer monoliths, hybrid organic-silica monoliths offer the combined advantages of mechanically strong stationary phases, simpler preparation protocols, resistance to swelling and shrinking in many solvents and better pH stability. Comprehensive data on the systematic characterization of the pore space morphology of hybrid organic-silica monoliths and...

The present research focuses on investigation of the catalytic behaviors of MgCl₂-SiO₂/TiCl₄/THF Ziegler-Natta (ZN) catalysts with fumed SiO₂ variously treated with silane compounds. The non-treated silica (NTS) and other silicas treated with dimethylsilicone fluid (TSDMSF), dimethyldichlorosilane (TSDMDCS), and hexamethyl-disilazane (TSHMDS) were employed. It was found that the Cat-TSDMDCS and...

Micro silica (MS) is an extremely fine, spherical powder that is used as an additive for improving concrete performance. It is obtained as a by product of silicon metal and ferrosilicon alloy production.  Due to its pozzolanic nature, micro silica can be used to enhance the qualities of both  fresh  and  hardened  concrete. Addition of micro silica into the concrete as a cement rep...

Occupational exposure to crystalline silica is a well-established occupational hazard. Once in the lung, crystalline silica particles can result in the activation of alveolar macrophages potentially leading to silicosis, a fibrotic lung disease. Because the activation of alveolar macrophages is the beginning step in a complicated inflammatory cascade, it is necessary to define the particle char...

Monodisperse, spherical, polyethylene glycol (PEG)-coated silica nanoparticles have been prepared at room temperature and characterized for the purpose of biomedical applications. The particles were synthesized by the hydrolysis of tetramethyl orthosilicate (TMOS) in alcohol media under catalysis by ammonia, and their size can range from about 50-350 nm in diameter. We studied the particle size...

1. Introduction Mesoporous materials with ordered arrays of uniform nanochannels of a controllable size have wide-ranging applications, one of which is membrane separation. In order to be used as a membrane for size-exclusive separation of molecules, it is necessary to synthesize a defect-free structure with continuous nanoporosity. Mesoporous silica and porous anodic alumina have been extensiv...

In this paper, optical properties of coupled silica disk microresonators are investigated. The spectral response and the light intensity distribution along the coupled disks were measured. It was found that the distribution depends on the particular excited resonance, which can be attributed to the formation of normal modes of the coupled resonator system. A developed theoretical model gives qu...