The reaction of 3-mercaptopropylsilica (MPS) and chlorosulfonic acid in chloroform afforded silica bonded S-sulfonic acid (SBSSA), which was used as a catalyst for the room temperature synthesis of quinoxaline derivatives from 1,2-diamino compounds and 1,2-dicarbonyl compounds. The catalyst could be recycled and reused several times without any loss of efficiency.

Highly ordered mesoporous organic-inorganic hybrid silica thin films with covalently bonded, positively chargeable -NH2 terminal groups were synthesized by evaporation induced self-assembly of tetraethoxysilane, 3-aminopropyl-triethoxysilane, and a nonionic surfactant under acid conditions and characterized using TEM, GISAXS, FTIR, SAW-based N2 sorption, and TGA.

Peptide mixtures, arising from such diverse sources as tissue extracts, urine or proteolysis, are usually fractionated and characterized by a combination of ion-exchange chromatography, gel-exclusion chromatography and/or electrophoresis. Appropriate combinations of these methods will normally yield a homogeneous product, but their costs, detection limits, analyses times and yields vary. The re...

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...

Current understanding of the brittleness of glass is limited by our poor understanding and control over the microscopic structure. In this study, we used a pressure quenching route to tune the structure of silica glass in a controllable manner, and observed a systematic increase in ductility in samples quenched under increasingly higher pressure. The brittle to ductile transition in densified s...

Multi-functional nanoparticles possessing magnetic, fluorescence and transition metal ion response properties were prepared and characterized. The particles have a core/shell structure that consists of silica-coated magnetic Fe₃O₄ and 2,6-diaminopyridine anchored on the silica surface via organic linker molecules. The resultant nanoparticles were found by transmission electron microscopy to be ...

We propose a joining process using femtosecond laser micro-welding to reinforce a direct bond. The process, which is executed at ambient temperature and can be applied to both similar and dissimilar material combinations, consists in inscribing weld lines in a closed loop forming a sealing pattern at the outskirts of the direct bond, thus preventing it from lifting off. We first characterized t...

One of the fundamental attributes a liquid chromatography column is its stability when exposed to acidic and basic mobile phases. However, there have been relatively few reports date on hydrophilic interaction (HILIC) columns. Here, we report results evaluations carried out for HILIC columns packed with ethylene-bridged hybrid or silica particles using accelerated conditions, employing 100% aqu...