Dislodging

If during the steam-distillation the />-tolunitrile tends to crystallise in the condenser, it is usually sufficient to increase the amount of steam momentarily in order to melt and dislodge the nitrile alternatively... 

Hydrolysis of benzanilide. Place 5 g. of benzanilide and 50 ml. of 70 per cent, sulphuric acid in a small flask fitted with a reflux condenser, and boU gently for 30 minutes. Some of the benzoio acid will vapourise in the steam and solidify in the condenser. Pour 60 ml. of hot water down the condenser this will dislodge and partially dissolve the benzoic acid. Cool the flask in ice water filter off the benzoic acid (anifine sulphate does not separate at this dilution), wash well with water, drain, dry upon filter paper, and identify by m.p. (121°) and other tests. Render the filtrate alkaline by cautiously adding 10 per cent, sodium hydroxide solution, cool and isolate the aniline by ether extraction. Recover the ether and test the residue for anifine (Section IV,100). 

Figure 2.7 shows a representation of this situation. The ordinate is an energy axis and the abscissa is called the reaction coordinate and represents the progress of the elementary step. In moving from P to H, the particle simply moves from one equilibrium position to another. In the absence of any external forces, the energy of both the initial and final locations should be the same as shown by the solid line in Fig. 2.7. Between the two minima corresponding to the initial and final positions is the energy barrier arising from the dislodging of the particles neighboring the reaction path from their positions of minimum energy.

Mechanical Cake Removal. This method is used in the American version of the dynamic filter described under cross-flow filtration with rotating elements, where turbine-type rotors are used to limit the cake thickness at low speeds. The Exxflow filter, introduced in the United Kingdom, is described in more detail under cross-flow filtration in porous pipes. It uses, among other means, a roUer cleaning system which periodically roUs over a curtain of flexible pipes and dislodges any cake on the inside of the pipes. The cake is then flushed out of the curtain by the internal flow. 

Dislodging of Cake by Reverse Flow. Intermittent back-flushing of the filter medium can also be used to control cake growth, leading to filtration through thin cakes in short cycles. Conventional vacuum or pressure filters can be modified to counter the effects of the forces during the back-flush (23,24). 

SEP mixers are hori2ontaHy installed on the side of the tank and near the bottom. By rotating the propeller, a spiralling jet is produced (Pig. 27) near the tank floor which provides the desired thmst to dislodge and entrain the sediments. SEP mixers should be designed to provide the suspension velocity at the farthest distance on the tank floor. 

Pipera2ine causes flaccid paralysis of Jiscaris by blocking the worms abiUty to respond to acetylcholine, thus dislodging the worms from thek... 

Surfa.cta.nt, The primary purpose of a surfactant in toothpaste is to create a foam while the teeth are bmshed. This foam provides an enjoyable sensation. Secondarily, the surfactant helps remove material dislodged by the toothbmsh, and it may have minor effects on plaque accumulation (see Surfactants). 

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