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Inside-out

The preparation of a urethane acrylate according to the inside-out technology starts with the polymeric diol. The reactor is charged with the diisocyanate, catalyst, and stabilizer. Now the diol is added slowly and a strong exothermic reaction starts. The rate of isocyanate addition is generally used to control the reaction exotherm in such a way that the temperature does not exceed 45°C. The control of this exotherm is especially important when IPDI is used as diisocyanate. For a higher se- [Pg.893]


Lonally, the templates were chosen by trial and error or exhaustive enumeration. A itafional method named ZEBEDDE (ZEolites By Evolutionary De novo DEsign) en developed to try to introduce some rationale into the selection of templates et al. 1996 Willock et al. 1997]. The templates are grown within the zeolite by an iterative inside-out approach, starting from a seed molecule. At each jn an action is randomly selected from a list that includes the addition of new (from a library of fragments), random translation or rotation, random bond rota-ing formation or energy minimisation of the template. A cost function based on erlap of van der Waals spheres is used to control the growth of the template ale ... [Pg.710]

Quench. Attempts have been made to model this nonisotherma1 process (32—35), but the complexity of the actual system makes quench design an art. Arrangements include straight-through, and outside-in and inside-out radial patterns (36). The optimum configuration depends on spinneret size, hole pattern, filament size, quench-chamber dimensions, take-up rate, and desired physical properties. Process continuity and final fiber properties are governed by the temperature profile and extension rate. [Pg.317]

The initial version of the inside-out method was developed for rapid calculations of simple and complex distillation, absorption, and... [Pg.1288]

Example 7 Calculation of Inside Out Method For the conditions of the simple distillation column shown in Fig, 13-55, obtain a converged solution by the inside-out method, using the SRK eqiiation-of-state for thermodynamic properties (in the outer loop),... [Pg.1289]

At this point in the inside-out method, the revised column profiles of temperature and phase compositions are used in the outer loop with the complex SRK thermodynamic models to compute updates of the approximate K and H constants. Then only one inner-loop iteration is required to obtain satisfactory convergence of the energy equations. The K and H constants are again updated in the outer loop. After one inner-loop iteration, the approximate K and H constants are found to be sufficiently close to the SRK values that overall convergence is achieved. Thus, a total of only 3 outer-loop iterations and 4 inner-loop iterations are required. [Pg.1289]

To illustrate the efficiency of the inside-out method to converge this example, the results from each of the three outer-loop iterations are summarized in the following tables ... [Pg.1289]

From these tables, it is seen that the stage temperatures and total liquid flows are already close to the converged solution after only one outer-loop iteration. However, the composition of the bottoms product, specifically with respect to the lightest component, C, is not close to the converged solution until after two iterations. The inside-out method does not always converge so dramatically, but is usually quite efficient,... [Pg.1289]

Baird [Comp. Chem. Engng., 9, 593 (1985)]. Since then, they have been applied successfully to problems involving interlinked distillation (Wayburn and Seader, op. cit.), azeotropic and three-phase distillation [Kovach, 111 and Seider, Comp. Chem. Engng., 11,593(1987)], and reac tive distillation [Chang and Seader, Comp. Chem. Engng., 12, 1243 (1988)], when SC and inside-out methods have failed. Today, many computer-aided distillation-design and simulation packages include continuation techniques to make the codes more robust. [Pg.1290]

The calculations were made with the RATEFRAC program and comparisons were made with the compamon RADFRAC program, which utilizes the inside-out method for an eqiiilibniim-based model. [Pg.1292]

Introduction Ask any chemical engineer who has had some plant experience what he or she knows about vacuum and the engineer will probably smile and tell some tale about some piece of eqiiip-ment that tried to turn itself inside out. Usually no one was hurt, and often there was no massive leakage—but not always ... [Pg.2335]

The property of chirality is determined by overall molecular topology, and there are many molecules that are chiral even though they do not possess an asymmetrically substituted atom. The examples in Scheme 2.2 include allenes (entries 1 and 2) and spiranes (entries 7 and 8). Entries 3 and 4 are examples of separable chiral atropisomers in which the barrier to rotation results from steric restriction of rotation of the bond between the aiyl rings. The chirality of -cyclooctene and Z, -cyclooctadiene is also dependent on restricted rotation. Manipulation of a molecular model will illustrate that each of these molecules can be converted into its enantiomer by a rotational process by which the ring is turned inside-out. ... [Pg.82]

Membrane systems consist of membrane elements or modules. For potable water treatment, NF and RO membrane modules are commonly fabricated in a spiral configuration. An important consideration of spiral elements is the design of the feed spacer, which promotes turbulence to reduce fouling. MF and UF membranes often use a hollow fiber geometry. This geometry does not require extensive pretreatment because the fibers can be periodically backwashed. Flow in these hollow fiber systems can be either from the inner lumen of the membrane fiber to the outside (inside-out flow) or from the outside to the inside of the fibers (outside-in flow). Tubular NF membranes are now just entering the marketplace. [Pg.358]

Stukkatur, /. stucco work plastering, stillpen, v.t. turn upside down (or inside out) put (over or upon). [Pg.435]

Umkehr,/. reversal return sudden change. Umkehrbad, n. (Photog.) reversing bath, uinkehrbar, a. reversible, invertible, capable of being turned about, over, or inside out. Umkehrbarkeit, /. reversibility, invertibility. umkehren, v.t. turn round, about, over, or inside out invert reverse. — .i. turn round... [Pg.462]

Cylindrical batteries can be classified into two basic types one with a spiral structure, and one with an inside-out structure. The former consists of a thin, wound cathode and the lithium anode with a separator between them. The latter is constructed by pressing the cathode mixture into a high-density cylindrical form. Batteries with the spiral construction are suitable for high-rate drain, and those with the inside-out construction are suitable for high energy density. [Pg.35]

Li-Mn02 batteries are available in a variety of shapes and construction [30] in accordance with their particular use. Figure 32 shows various applications of lithium batteries based on their drain current. Coin-type batteries are generally used for low-rate drain. Cylindrical batteries with the inside-out construction can serve as a... [Pg.36]

Table 2. Specifications of cylindrical, inside-out construction, manganese dioxide-lithium batteries... Table 2. Specifications of cylindrical, inside-out construction, manganese dioxide-lithium batteries...
Integrins, selectins, cadherins, claudins and other cell adhesion molecules are involved in the interaction of cells with other cells or with extracellular matrix components. Some of them also serve as receptors by inducing outside-in or additional inside-out signaling. [Pg.340]


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Comparing Inside-out with Outside-in

Inside

Inside-Out Algorithms

Inside-Out versus Outside-In Methods

Inside-out NMR

Inside-out configuration

Inside-out membrane patches

Inside-out methods

Inside-out signaling

Inside-out technique

Inside-out vesicles

Thylakoid inside-out vesicle

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