Silica bubbles

Buoyant silica bubbles were employed as capture substrates in a cholera SERS immunoassay (Schmit et al. 2012). Silica bubbles were silanized and then functionalized with an anti-cholera toxin antibody. Au NPs were used as SERS... 

To a solution of indoline (20 mM in MeOH) was added Co(salen) (0.10 equiv.) and O2 was bubbled through the suspension at 25°C. After 1 h the suspension became homogeneous and the solvent was removed in vacuo and the product purified by chromatography on silica gel. 

Transparent Vitreous Silica. Clear, transparent, bubble-free vitreous sihca may be obtained by melting natural quart2 minerals, ie, fused quart2, by flame or plasma vapor deposition (synthetic fused siUcas), and by sol—gel processing. 

Hydrophobic silica defoamers work on a basis which may not be chemical at all. They are basically finely divided sohd sihca particles dispersed in a hydrocarbon or silicone oil which sei ves as a spreading vehicle. Kulkarni [Ind. Eng. Chem. Fundam., 16, 472 (1977)] theorizes that this mixture defoams by the penetration of the silica particle into the bubble and the rupture of the wall. Table 14-23 hsts major types of defoamers and typical applications. 

N-(n-Butyl)>a-methylene-3-lactam (2). CO was bubbled through Pd(OAc)2 or Pd(Ph3P)4 (0.136 mmol) in CH2CI2 (4 mL) After 2 rmn PhsP (0 54 mmol) n CH2CI2 (2 mL) is added followed by aziridine 1 In CH2CI2 After 40 h, the solvent was removed in vacuum and the residue purified by prep tic (silica gel, hexane ElOAc 8 1) to yield 2 (79%)... 

Carbonate ionophore I [ETH 6010] (heptyl 4-trifluoroacetylbenzoate) [129476-47-7] M 316.3, b 170°/0.02 Torr, d 0.909. Purified by flash chromatography (2g of reagent with 30g of Silica Gel 60) and eluted with EtOAc/hexane (1 19). The fractions that absorbed at 260nm were pooled, evapd and dried at room temp (10.3 Torr). The oily residue was distd in a bubbled-tube apparatus (170°/0.02 Torr). Its IR (CHCI3) had peaks at 1720, 1280, 940cm and its sol in tetrahydrofuran is 50mg/0.5mL. It is a lipophilic neutral ionophore selective for carbonate as well as being an optical humidity sensor. [Anal Chim Acta 233 41 1990.]... 

If one amino group in o-phenylenediamine is converted to an amide group by formic acid, the intermediate benzimidazole is formed. This reaction, conducted with a wide range of reactants, produces resins (polybenzimidazoles) used as high-temperature adhesives for laminates in the aerospace industry. Heat insulation is made by including tiny bubbles of silica and all... 

Permeability control Silica flour, gas bubble-producing additives ... 

Arsenic trioxide reacts violently and nitrogen oxide ignites in excess fluorine. Bubbles of sulfur dioxide explode separately on contacting fluorine, while addition of the latter to sulfur dioxide causes an explosion at a certain concentration [1], Reaction of fluorine with dinitrogen tetraoxide usually causes ignition [2], Interaction with carbon monoxide may be explosive. Anhydrous silica incandesces in the gas, and interaction with liquid fluorine at — 80°C is explosive [3,4], Boron trioxide also incandesces in the gas [3],... 

TLC was performed on silica (Merck silica gel 60 F-254 0.25-mm thickness) with EtOAc/hexanes (1 4). The complex remains at the baseline (Rf = 0), while the ligand has an Rf = 0.85. If ligand consumption is not complete, bubbling of air through the solution and heating are continued while the reaction is monitored every 20 min... 

The ketone (1 mmol) in PhMe (10 ml), Et,PO, (0.2 g, 1.2 mmol) and the catalyst (0.05 mmol) are added to aqueous NaOH (50%, 2.5 ml) and 02 is bubbled through the vigorously stirred solution until all of the ketone is consumed. H,0 (10 ml) is then added and the aqueous phase is separated and extracted with C6H6 (2x5 ml). The combined organic solutions are washed sequentially with 10% aqueous HCI, H20, and brine, dried (Na2S04), and evaporated. Chromatography from silica yields the a-hydroxyketone. 

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