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Total condenser analogy

For the case where the column has a total condenser, the above procedures are modified in a manner analogous to that shown in Chap. 5. [Pg.406]

With the equimolal overflow assumption mentioned above, all of the vapor rales (Vn) throughout the stripping section are equal to V5, and all of the liquid rates (Z ) are equal to Ls- Analogously, all V beginning from the top feed tray throughout the rectifying section and total condenser are Vr, and all L are equal to Lr. [Pg.46]

Diastereomer analysis on the unpurified aldol adduct 52b revealed that the total syn anti diastereoselection was 400 1 whereas enantioselective induction in the syn products was 660 1. On the other hand, Evans in some complementary studies also found that in the condensation of the chiral aldehyde 53 with an achiral enolate 56a only a slight preference was noted for the anti-Cram aldol diastereomer 58a (58a 57a = 64 36). In the analogous condensation of the chiral enolate 56b. however, the yn-stereoselection was approximately the same (57b 58b > 400 1) as that noted for enolate 49 but with the opposite sense of asymmetric induction (Scheme 9.17). Therefore, it can be concluded that enolate chirality transfer in these systems strongly dominates the condensation process with chiral aldehydes. [Pg.255]

Capillary condensation can be illustrated by the model of a conical pore with a totally wetting surface (Fig. 2.12). Liquid will immediately condense in the tip of the pore. Condensation continues until the bending radius of the liquid has reached the value given by the Kelvin equation. The situation is analogous to that of a bubble and we can write... [Pg.17]

The power of this cycloaddition method is clearly illustrated in its application to the synthesis of 80 (Scheme 2.22), a known intermediate for the total synthesis of cyanocycline A (81) and bioxalomycin (32 (82) 43 The condensation of aldehyde 78 and 75 in neat methyl acrylate (27) took place to afford the pyrrolidine 79 in 74% yield as a single stereoisomer.44 This compound was then converted into 80 in 12 steps. The method has also been applied to the synthesis of a number of analogs of 81 and 82 with... [Pg.56]

Now from (2) it can be shown that for sufficiently large s, the total number of quanta N=2njc increases proportionally to the total rate of supply s. Equation (4) then shows that a critical rate of supply Sq, exists, such that for s>Sq something analogous to Einstein condensation of a Bose gas must occur. This implies that p, which acts as chemical potential, must approach very closely such that the occupation, n, of becomes very large. Since represents a normal mode, it follows that this excitation is coherent. [Pg.215]

Lippmann s proof was essentially as follows. The interface was supposed to be analogous to a parallel plate condenser with a difference of potential A between the plates the work required to increase the charge on the plates by dQ is dQ.A. Work is also required to increase the area, owing to the surface tension hence the total reversible work is... [Pg.344]

A dynamical temperature is an analogy of the temperature in a condensed phase. Seko et al. proposed an alternative definition of temperature for clusters to satisfy the statistical mechanics. Since the meaning of the temperature itself is out of the topics in this work, we will just use the dynamical temperature defined in Eq. (5). Figure 4 shows the relationship between the total energy from the... [Pg.135]

In the vapor-pressure osmometer, there is no membrane. Two matched thermistors are located in a thermostated chamber that is saturated with solvent vapor (Fig. 4.8). With a hypodermic syringe a drop of solution is placed on one thermistor and a drop of solvent on the other thermistor. The solution has a lower vapor pressure than the solvent at the same temperature, and so the solvent vapor condenses on the solution droplet. The solution droplet, therefore, starts getting diluted as well as heated up by the latent heat of condensation of solvent condensing on it. Owing to the temperature rise and increased dilution, the vapor pressure of the solution droplet increases steadily. The process of condensation and the resultant temperature rise continues till the vapor pressure of the solution droplet at the new elevated temperature becomes equal to that of the pure solvent at the original temperature. In a steady state, the total rise in temperature AT can be related by an analog of Eq. (4.67) ... [Pg.259]


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See also in sourсe #XX -- [ Pg.117 ]




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