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Basic scheme

The basic scheme of this algorithm is similar to cell-to-cell mapping techniques [14] but differs substantially In one important aspect If applied to larger problems, a direct cell-to-cell approach quickly leads to tremendous computational effort. Only a proper exploitation of the multi-level structure of the subdivision algorithm (also for the eigenvalue problem) may allow for application to molecules of real chemical interest. But even this more sophisticated approach suffers from combinatorial explosion already for moderate size molecules. In a next stage of development [19] this restriction will be circumvented using certain hybrid Monte-Carlo methods. [Pg.110]

Propylene oxide-based glycerol can be produced by rearrangement of propylene oxide [75-56-9] (qv) to allyl alcohol over triUthium phosphate catalyst at 200—250°C (yield 80—85%) (4), followed by any of the appropriate steps shown in Figure 1. The specific route commercially employed is peracetic acid epoxidation of allyl alcohol to glycidol followed by hydrolysis to glycerol (5). The newest international synthesis plants employ this basic scheme. [Pg.347]

The purified acid is recovered from the loaded organic stream by contacting with water in another countercurrent extraction step. In place of water, an aqueous alkafl can be used to recover a purified phosphate salt solution. A small portion of the purified acid is typically used in a backwashing operation to contact the loaded organic phase and to improve the purity of the extract phase prior to recovery of the purified acid. Depending on the miscibility of the solvent with the acid, the purified acid and the raffinate may be stripped of residual solvent which is recycled to the extraction loop. The purified acid can be treated for removal of residual organic impurities, stripped of fluoride to low (10 ppm) levels, and concentrated to the desired P2 s Many variations of this basic scheme have been developed to improve the extraction of phosphate and rejection of impurities to the raffinate stream, and numerous patents have been granted on solvent extraction processes. [Pg.328]

The basic schemes for electrical power generation and combined heat and power have been identified in the earlier sections of this chapter. When assessing the alternatives to meet a specific project need, many factors will strongly influence the size, number, and type of generator as well as its specification and scope. While it is not intended to cover all of these aspects, the more important issues are discussed. [Pg.186]

The basic requirement for cellulose dissolution is that the solvent is capable of interacting with the hydroxyl groups of the AGU, so as to eliminate, at least partially, the strong inter-molecular hydrogen-bonding between the polymer chains. There are two basic schemes for cellulose dissolution (i) Where it results from physical interactions between cellulose and the solvent (ii) where it is achieved via a chemical reaction, leading to covalent bond formation derivatizing solvents . Both routes are addressed in details below. [Pg.113]

The basic scheme for the numerical solution is the same as that used for the 1 -D model, except that in this case the solid temperature field used to solve the DAE system for each monolith channel must be calculated from the three-dimensional solid-phase energy balance equation. The three-dimensional energy balance equation can be solved by a nonlinear finite element solver (such as ABAQUS) for the solid-phase temperature field while a nonlinear finite difference solver for the DAE system calculates the gas-phase temperature and... [Pg.14]

Fig. 10. Comparison of a typical homogeneous immunoassay (left) with a heterogeneous format (right). Depending on choice of reagents, there are many possible variations on these basic schemes... Fig. 10. Comparison of a typical homogeneous immunoassay (left) with a heterogeneous format (right). Depending on choice of reagents, there are many possible variations on these basic schemes...
Heterogeneous electron reactions at liquid liquid interfaces occur in many chemical and biological systems. The interfaces between two immiscible solutions in water-nitrobenzene and water 1,2-dichloroethane are broadly used for modeling studies of kinetics of electron transfer between redox couples present in both media. The basic scheme of such a reaction is... [Pg.28]

Fig. 1.16 Typical motion-compensated, velocity encoding imaging sequence. The basic scheme from Figure 1.11 is amended by additional compensating gradient pulses for the read, phase and slice directions. The velocity encoding pair of gradient pulses of duration 8 and separation A is drawn on a separate line in reality, it is applied along any of the three... Fig. 1.16 Typical motion-compensated, velocity encoding imaging sequence. The basic scheme from Figure 1.11 is amended by additional compensating gradient pulses for the read, phase and slice directions. The velocity encoding pair of gradient pulses of duration 8 and separation A is drawn on a separate line in reality, it is applied along any of the three...
Relatively simple variants of this basic scheme... [Pg.22]

This scheme is introduced in [4, 8], and also used in [7]. It differs from the basic scheme in the preprocessing and hiding operations. A secure hash function is applied to the signature before embedding, in order to reduce its size. The locations of the embedded CLBs are also fingerprinted with the identity of the user in order to trace back the origin of mis-appropriation. Additional hiding operations are also put in. [Pg.9]

Even before the Flade potential the dissolution of iron is a complex process which has been thoroughly investigated by Epelboin and coworkers with AC impedance. The starting point is the same basic scheme as that proposed for chlorine evolution ... [Pg.328]

A basic scheme of the apparatus that has been used by Cole-Hamilton et al. for the continuous Rh-catalysed hydroformylation in the system [BMIM][PF6]/scC02 is shown in Figure 7.9. [Pg.200]

Figure 7.9. Basic scheme of the apparatus used for biphasic Rh-catalysed hydroformylation in an IL/SCCO2... Figure 7.9. Basic scheme of the apparatus used for biphasic Rh-catalysed hydroformylation in an IL/SCCO2...
The basic scheme for MAPK cascades is shown in Figure 23-4. MAPK is part of a phosphorelay system composed of three sequentially activated kinases [13]. MAPK, inactive under basal conditions, is activated by phosphorylation by another protein kinase, termed... [Pg.396]

The simple reaction scheme outlined in Scheme 2 easily accommodates the results obtained in the investigation of XA. The basic scheme is just the same as it is for BA except that the relative energies of the singlet and triplet states of the carbene are reversed. All of the evidence points to a singlet ground state for XA. This includes the absence of an epr signal, the nearly diffusion-controlled formation of ether in direct and sensitized experiments, the stereospecific cyclopropanation, and the absence of a rapid reaction of the carbene with 02. [Pg.340]

Electron-transfer reactions at liquid-liquid interfaces involve redox couples on each side of the interface. The basic scheme is (see Fig. 12.5) ... [Pg.160]

Nomenclature, 17 384-413 basic scheme of, 17 384-385 biochemical, 17 401-402 computerized approaches to, 17 400-401 elastomer, 21 761t enzyme, 10 258-260 for ionic liquids, 26 840-841 glossaries related to, 17 404 inorganic, 17 387-394 macromolecular (polymers), 17 403 404 organic, 17 394-401 polymer, 20 390-395 pump, 21 88 quinone, 21 236-237 reactor technology, 21 358 related to mass transfer, 15 731-737 reverse osmosis, 21 674-676 Society of Rheology, 21 704 spray-related, 23 199t systematic, 17 394... [Pg.629]

Figure 9.17 The basic schemes of (a) bidisperse (biporous) porous solid structure 1, nonporous primary particles, 2, aggregates of primary particles (secondary particles), 3, porous solid (granule, grain, pallet, etc.) (b) a bed of granules in a catalytic reactor 4. Figure 9.17 The basic schemes of (a) bidisperse (biporous) porous solid structure 1, nonporous primary particles, 2, aggregates of primary particles (secondary particles), 3, porous solid (granule, grain, pallet, etc.) (b) a bed of granules in a catalytic reactor 4.
The most useful methods for the formation of C-C bonds are based on the addition of C-nucleophiles to carbonyl compounds. Among the many variations of this basic scheme phosphorus ylides, capable of olefinating aldehydes or ketones in a single step, have proven to be exceedingly valuable reagents in organic synthesis. [Pg.125]

Each element is assumed to be composed of the basic scheme described in model 6, and to transmit the signal Aj(t) to the subsequent one. When 0 < t < 60, high-frequency input is introduced to the first element and low-frequency input is introduced to the fourth. When 60 < f < 120, low-frequency input is introduced to the first element and high-frequency input is introduced to the fourth. [Pg.15]

Technology licensors recently made significant advances in process design and they now offer many variations and improvements of these basic scheme, however the discussion below only examines these four basic designs because their reaction environments encompass all conditions that impact the elementary catalytic steps and their implications on catalyst and materials requirements. From a catalytic perspective these four configurations may be grouped into two sets which differ significantly in the reaction environments the catalysts operate in as discussed in the section below. [Pg.561]


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