Stage three

Figure 3.12 Three possible arrangements for a three-stage evaporator.

Many other mixed-feed arrangements are possible which combine the individual advantages of each type of arrangement. Figure 3.13 shows a three-stage evaporator in temperature-enthalpy terms, assuming that inlet and outlet solutions are at saturated conditions... 

Figure 3.14 Variation of total cost with number of stages indicates that three stages is the optimal number for a stand-alone system in this case.

Figure 15.1a shows a single-stage evaporator represented on both actual and shifted temperature scales. Note that in shifted temperature scale, the evaporation and condensjftion duties are shown at different temperatures even though they are at the same actual temperature. Figure 15.16 shows a similar plot for a three-stage evaporator. 

Consider the three-stage evaporator against a background process... 

The A/ 100 corresponds to the difference between the RON of the motor fuel and that of the fraction distilled at 100°C. The determination is carried out in three stages ... 

Figure 6. Three stages of the fatigue damage growth in composite laminates [2]...

Figure C3.6.7(a) shows tire u= 0 and i )= 0 nullclines of tliis system along witli trajectories corresponding to sub-and super-tlireshold excitations. The trajectory arising from tire sub-tlireshold perturbation quickly relaxes back to tire stable fixed point. Three stages can be identified in tire trajectory resulting from tire super-tlireshold perturbation an excited stage where tire phase point quickly evolves far from tire fixed point, a refractory stage where tire system relaxes back to tire stable state and is not susceptible to additional perturbation and tire resting state where tire system again resides at tire stable fixed point.

DENDRAL followed a three-stage procedure. In the first phase, the so-called plan, prior knowledge, and heuristics were used to deduce a set of constraints. Constraints could be, for example, the exemption of large sets of candidate solutions or the suggestion for a extensive search over limited classes of solutions. 

The velocity Verlet method is actually implemented as a three-stage procedure because, as can be seen from Equation (7.15), to calculate the new velocities requires the accelerations at both t and t + 8t. Thus in the first step the positions at f I- are calculated according to Equation (7.14) using the velocities and the accelerations at time t. The velocities at time t + 6t are then determined using ... 

The process whereby aldehydes are produced from arylmethyl (also alkyl and other) halides by the action of hexamine is known as the Sommelet reaction. The reaction is essentially the conversion of an amine into an aldehyde the hexamine serves the dual role of converting the halide into the amine and the amine into the aldehyde, but its function is different in the two steps. When starting from a halide, the reaction proceeds in three stages —... 

The objective of the Flory-Krigbaum theory is to find a quantitative expression for the placement probability n(d) of the two coils as a function of their separation d. There are three stages to the derivation ... 

Of the three stages outlined above, only the calculation of AG for the procesj in Fig. 8.11 warrants further discussion. Recalling that the volume of the shaded... 

Our objective now becomes finding an expression for P(0). The theory for P(0) proceeds through three stages ... 

This expression formalizes the anticipated conclusion that it is the difference in phase between light scattered by different segments that is responsible for the interference effect we seek to analyze. Equation (10.72) completes the first of the three stages in the development of P(0). 

The objective of the Zimm plot is to conduct all extrapolations on a single graph. The three-stage development of Fig. 10.14 is not typical, but it is intended to clarify the discussion. 

Manufacture. One commercial process features a three-stage saturation—rearomatization technique using benzene and fluorine gas as raw materials (73). Principal problems with this method are the complex nature of the process, its dependence on fluorine gas which is cosdy to produce, and the poor overall utilization of fluorine, because nearly one-half of the input fluorine is removed during the process. 

Commercial soy protein concentrates typically contain 70 to 72% cmde protein, ie, nitrogen x 6.25, dry wt basis. Soy protein isolates are prepared from desolventhed, defatted flakes. A three-stage aqueous countercurrent extraction at pH 8.5 is used to disperse proteins and dissolve water-soluble constituents. Centrifugation then removes the extracted flakes, and the protein is precipitated from the aqueous phase by acidifying with HCl at pH 4.5. 

Since GAs as diterpenes share many intermediates in the biosynthetic steps leading to other terpenoids, eg, cytokinins, ABA, sterols, and carotenoids, inhibitors of the mevalonate (MVA) pathway of terpene synthesis also inhibit GA synthesis (57). Biosynthesis of GAs progresses in three stages, ie, formation of / Akaurene from MVA, oxidation of /-kaurene to GA 2" hyde, and further oxidation of the GA22-aldehyde to form the different GAs more than 70 different GAs have been identified. 

Kinetics and Mechanisms. Early researchers misunderstood the fast reaction rates and high molecular weights of emulsion polymerization (11). In 1945 the first recognized quaHtative theory of emulsion polymerization was presented (12). This mechanism for classic emulsion preparation was quantified (13) and the polymerization separated into three stages. 

In 1986 Britannia Refined Metals (Northfleet, U.K.) introduced technology for the treatment of Parkes cmst, a triple alloy of Ag, Zn, Pb, which by 1992 had been adopted by seven lead refineries (22). The technology consists of a three-stage process in which the silver-rich cmst is first Hquated to reduce its lead content, then placed in a sealed furnace where the 2inc is removed by vacuum distillation and, finally, the silver—lead metal is treated in a bottom blown oxygen cupel (BBOC) to produce a Htharge slag and dorn metal. 

Vacuum Treatment. Milk can be exposed to a vacuum to remove low boiling substances, eg, onions, garlic, and some silage, which may impart off-flavors to the milk, particularly the fat portion. A three-stage vacuum unit, known as a vacreator, produces pressures of 17, 51—68, and 88—95 kPa (127, 381—508, and 660—711 mm Hg). A continuous vacuum unit in the HTST system may consist of one or two chambers and be heated by Hve steam, with an equivalent release of water by evaporation, or flash steam to carry off the volatiles. If Hve steam is used, it must be cuUnary steam which is produced by heating potable water with an indirect heat exchanger. Dry saturated steam is desired for food processing operations. 

In general, zeohte crystallization consists of three stages (/) formation of precursors, ie, building blocks that can generate nuclei (2) nucleation and (J) crystal growth. 

Many hydroperoxides have been prepared by autoxidation of suitable substrates with molecular oxygen (45,52,55). These reactions can be free-radical chain or nonchain processes, depending on whether triplet or singlet oxygen is involved. The free-radical process consists of three stages ... 

Fig. 15. Three stages of blow molding (a—c) A, air line B, die C, mold and D, parison. See text.

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