Fusing bubbles

As a glaze is fired, its structure changes continuously. Materials initially present decompose and fuse. Bubbles are formed and rise to the surface, and reaction takes place with the body under the glaze. The interface between the glaze and body is rough because of the differences in solubility in the body constituents. Mullite crystals develop at the interface of porcelain... 

Interfacial Forces. Neighboring bubbles in a foam interact through a variety of forces which depend on the composition and thickness of Hquid between them, and on the physical chemistry of their Hquid—vapor interfaces. For a foam to be relatively stable, the net interaction must be sufficiently repulsive at short distances to maintain a significant layer of Hquid in between neighboring bubbles. Otherwise two bubbles could approach so closely as to expel all the Hquid and fuse into one larger bubble. Repulsive interactions typically become important only for bubble separations smaller than a few hundredths of a micrometer, a length small in comparison with typical bubble sizes. Thus attention can be restricted to the vapor—Hquid—vapor film stmcture formed between neighboring bubbles, and this stmcture can be considered essentially flat. 

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. 

Europium oxide (EU2O3) nanorods have been prepared by the sonication of an aqueous solution of europium nitrate in the presence of ammonia. In this reaction, ammonium ions adsorbed on the Eu(OH)3 particles (formed due to the collapse of the bubbles) results in the formation of a monolayer which then fuse together by hydrogen bonding leading to the formation of nanorods [28]. 

The fused indolopyrrolizidine 137 can be transformed into the tetrahydropyrrolizinoquinolone 138 upon reaction with Bu OK while oxygen is bubbled into the solution. (This is an apparently general strategy for the oxidation of indoles.) Compound 138 may then be oxidized with w-chloroperbenzoic acid (MCPBA) to give the dihydropyrido-pyrrolizine 139 <1997TL2997> (Scheme 37). 

B stage orgchem An intermediate stage in a thermosetting resin reaction In which the plastic softens but does not fuse when heated, and swells but does not dissolve In contact with certain liquids. be, staj bubble point phys chem In a solution of two or more components, the temperature... 

Wet test meter, bubble tube, rotameter, and manometer Assorted spare parts pumps, fuses, orifices, etc. 

Several different analytical and ultra-micropreparative CEC approaches have been described for such peptide separations. For example, open tubular (OT-CEC) methods have been used 290-294 with etched fused silicas to increase the surface area with diols or octadecyl chains then bonded to the surface.1 With such OT-CEC systems, the peptide-ligand interactions of, for example, angiotensin I-III increased with increasing hydrophobicity of the bonded phase on the capillary wall. Porous layer open tubular (PLOT) capillaries coated with anionic polymers 295 or poly(aspartic acid) 296 have also been employed 297 to separate basic peptides on the inner wall of fused silica capillaries of 20 pm i.d. When the same eluent conditions were employed, superior performance was observed for these PLOT capillaries compared to the corresponding capillary zone electrophoresis (HP-CZE) separation. Peptide mixtures can be analyzed 298-300 with OT-CEC systems based on octyl-bonded fused silica capillaries that have been coated with (3-aminopropyl)trimethoxysilane (APS), as well as with pressurized CEC (pCEC) packed with particles of similar surface chemistry, to decrease the electrostatic interactions between the solute and the surface, coupled to a mass spectrometer (MS). In the pressurized flow version of electrochromatography, a pLC pump is also employed (Figure 26) to facilitate liquid flow, reduce bubble formation, and to fine-tune the selectivity of the separation of the peptide mixture. 

The activity of calcined HTs was determined in self-condensation reaction of acetone (J.T. Baker) by using a fixed bed catalytic reactor with an on-line GC. Prior to the catalytic test, catalysts were pretreated in-situ under nitrogen atmosphere at 450°C for 5h. Acetone was supplied to the reactor by bubbling nitrogen gas through the acetone container at 0 °C. The reaction temperature was established at 200 C. The products were analyzed by means of GC (Varian CP-3800) using a WCOT Fused silica column, equipped with a FID detector. 

The advantage with respect to reverse micelles lies in the fact that these bubbles fuse and mix with each other rather efficiently upon stirring. One example is given... 

Anhydrous AnalaR stannous chloride was distilled from A into the electrolytic cell, C, under a high vacuum after the whole apparatus had been baked out. Vessel A was sealed off at X, the stannous chloride fused by the heater H, and a 12 V DC potential applied across the terminals Jj and T Tj led to a gas-carbon rod serving as anode, to a Pt wire cathode. Bubbles of stannic chloride vapour rose from the anode. The first runnings were pumped out and then the system was sealed off at Y. Electrolysis was continued until sufficient stannic chloride had been condensed in the sample holder, S, which was removed from the system by being sealed off at Z. 

The existence of the nitryl ion in the presence of acidic substances suggested that nitrate ion in fused alkali nitrates might dissociate into N02+ and 0 2 ions (5). To determine the extent of the dissociation, it was necessary to develop an electrode potentiometrically responsive to either N02+ or 0 2. The only possibility for a reversible N02+ electrode that came to mind was nitrogen dioxide gas bubbling over platinum. This electrode did respond to N02+ in acidic solutions, but as ex-... 

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