Lippmann apparatus

It has long been known that the form of a curved surface of mercury in contact with an electrolyte solution depends on its state of electrification [108, 109], and the earliest comprehensive investigation of the electrocapillary effect was made by Lippmann in 1875 [110]. A sketch of his apparatus is shown in Fig. V-10. 

Metallic Zinc. Ancient metallurgists probably lost the volatile zinc metal as vapor because their apparatus was not designed for condensing it. E. O. von Lippmann, a great authority on the history of science, searched the writings of Aristotle, Plmy, and Dioscorides in vain for any mention of it, but an idol containing 87 5 per cent of that metal was found in a prehistoric Dacian ruin at Dordosch, Transylvania (2). 

Electrocapillary phenomena have been studied for a long time the apparatus shown in Figure 7.22 is essentially that used by G. Lippmann in 1875 in his comprehensive studies of electrocapillarity. We do not examine either the experimental or the theoretical aspects of this system in great detail however, an interpretation of the results that is more quantitative than that just outlined qualitatively is possible with relatively little additional effort. 

An alternative that is less resource-intensive than the flow loop is the flow wheel apparatus (Bakkeng and Fredriksen, 1994 Lippmann et al., 1994) shown in Figure 6.4b. The wheel (torus) is nominally a 2-5 in. (5.1-12.7 cm) pipe, 2 m in diameter that rotates at 0.3-5.0 m/s while filled with gas and less than 50 vol% liquid. Conceptually, the wheel is spun past the gas and liquid rather than the reverse. Therefore, the flow wheel apparatus does not require circulating devices such as pumps or compressors. Hydrate formation is deduced visually, or by a sharp increase in torque required to turn the wheel. Urdahl et al. (1995) and Lund et al. (1996) report good field transferability from results obtained with this apparatus. Pilot flow loops and flow wheels have been also used to simulate shut-in/start-up conditions (12 h stagnant period) and to test kinetic inhibitors (e.g., Palermo and Goodwin, 2000 Rasch et al., 2002). 

The enantiomorph, d-quinic acid, has been found only in the form of the racemate. Lippmann (68) dried the tops and leaves of sugar beets and found the racemate in the cooler parts of the drying apparatus. Eijkman (71) had previously shown that the lactone of Z-quinic acid, quinide, is racemized by heat. Hence Lippmann s racemate from sugar beets may be an artifact. The dextrorotatory form may be obtained from the racemate by resolution or by the action of microorganisms, the levorotatory form being destroyed (68),... 

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