Chain bubbling

Recommendations for p range from 1 to 1.5 and for q from 0 to 2. Rice et al. [62] concluded that this was due to the different regimes and recommended q values of 2, 1, 1/3 and 0 for chain bubbling, bubbling flow, chum-turbulent flow and slug flow, respectively. 

In view of the fact that chains of bubbles are formed, this regime is sometimes referred to as chain bubbling regime. The terminal rise velocity of a small discrete bubble is relatively very low. However, the drag on an individual bubble is affected by the presence of bubbles in its vicinity. The resulting hindrance increases with inaeasing number of bubbles or gas holdup. The drag and consequent turbulence is... 

In contrast, the ultrasonic irradiation of organic Hquids has been less studied. SusHck and co-workers estabHshed that virtually all organic Hquids wiU generate free radicals upon ultrasonic irradiation, as long as the total vapor pressure is low enough to allow effective bubble coUapse (49). The sonolysis of simple hydrocarbons (for example, alkanes) creates the same kinds of products associated with very high temperature pyrolysis (50). Most of these products (H2, CH4, and the smaller 1-alkenes) derive from a weU-understood radical chain mechanism. 

Interaction of Solids With Flotation Reagents. For flotation to occur with the aid of reagents, such compounds must adsorb at the sohd—hquid interface unless the soHd to be floated is naturally hydrophobic. In this latter case only depression can be attempted by the use of additional ions or depressants that hinder bubble—particle adhesion. Frothers (typically long-chain alcohols) and/or modifying agents such as hydrocarbon oils can, however, be used to enhance the collection of naturally hydrophobic soflds such as M0S2, talc, or plastics. 

Branched-chain alkenes react with hydrazine under acidic conditions to give the corresponding alkyl hydrazine. For example, isobutylene bubbled through an aqueous solution of hydrazine and HCl gives /-butyUiydrazine in reasonably good yields (64). 

The pH of the pulp to the flotation cells is carefliUy controlled by the addition of lime, which optimizes the action of all reagents and is used to depress pyrite. A frother, such as pine oil or a long-chain alcohol, is added to produce the froth, an important part of the flotation process. The ore minerals, coated with an oily collected layer, are hydrophobic and collect on the air bubbles the desired minerals float while the gangue sinks. Typical collectors are xanthates, dithiophosphates, or xanthate derivatives, whereas typical depressants are calcium or sodium cyanide [143-33-9] NaCN, andlime. 

The structure of whipped cream is quite complex. A coating of milk protein surrounds small globules of milk fat containing both solid and liquid fats. These globules stack into chains and nets around air bubbles. The air bubbles are also formed from the milk proteins, which create a thin membrane around the air pockets. The three-dimensional network of joined fat globules and protein films stabilizes the foam, keeping the whipped cream stiff. 

The foam volume and stability of alcohol sulfates is relatively increased in hard water compared to soft water. The amount and quality of foam is dependent on the alkyl length. Sulfates with C12-C,4 alkyl chains produce the richest creamy foam with small bubbles. C8-C10 alcohol sulfates are foam depressants and C16-C18 alcohol sulfates are poor foaming surfactants. Foams produced by alcohol sulfates are also relatively stable in the presence of sebum. Sodium and ammonium alcohol sulfates foam better than triethanolamine alcohol sulfates. Alcohol ether sulfates produce lighter foams than those of alcohol... 

The combustion of H2 and 02 in the cavitation bubble [20] and the consumption of these gases, when in the ratio of 1 3 and 2 1, favoured the maximum formation of H2O2. Since the conditions of gases in a cavitating bubble were different from those under flame, the mechanism could not precisely be the same. The intermediates of chain reactions rapidly reached cooler interfacial region of the bubble and therefore did not allow the chain length to go beyond 10 steps. Fe2+ ions present in the... 

---