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Tion of the

Genetic algorithms can also be used to perform molecular docking [Judson et d. 1994 Jont et d. 1995b Oshiro et d. 1995]. Each chromosome codes not only for the internal conform tion of the ligand as described in Section 9.9.1 but also for the orientation of the ligand withi the receptor site. Both the orientation and the internal conformation will thus vary as th populations evolve. The score of each docked structure within the site acts as the fitnes function used to select the individuals for the next iteration. [Pg.679]

Bron C and J Kerbosch 1973. Algorithm 475. Finding All Cliques of an Undirected Graph. Communia tions of the ACM 16 575-577. [Pg.737]

Aromatic alcohols are insoluble in water and usually burn with a smoky flame. Their boiling points are comparatively high some are solids at the ordinary temperature. Many may be oxidised by cautious addi-tion of dilute nitric acid to the corresponding aldehyde upon neutralis-tion of the excess of acid, the aldehyde may be isolated by ether extraction or steam distillation, and then identified as detailed under Aromatic Aldehydes, Section IV,135. [Pg.817]

Although several experimental data concerning the functionalization of cumulenic anions are availab. a (for a review see Ref. 10) (Table I), it remains difficult to predict the compos tion of the product of a particular reaction on a rationalistic basis. Especially the outcome of reactions with carbonyl compounds seems to be... [Pg.28]

The 2-substituted 3-acylindoles 579 are prepared by carbonylative cycliza-tion of the 2-alkynyltrifluoroacetanilides 576 with aryl halides or alkenyl tri-flates. The reaction can be understood by the aminopalladation of the alkyne with the acylpalladium intermediate as shown by 577 to generate 578, followed by reductive elimination to give 579[425]. [Pg.207]

Hthiated 4-substituted-2-methylthia2oles (171) at -78 C (Scheme 80). Crossover experiments at—78 and 25°C using thiazoles bearing different substituents (R = Me, Ph) proved that at low temperature the lithioderivatives (172 and 173) do not exchange H/Li and that the product ratios (175/176) observed are the result of independent metala-tion of the 2-methyl and the C-5 positions in a kinetically controlled process (444). At elevated temperatures the thermodynamic acidities prevail and the resonance stabilized benzyl-type anion (Scheme 81) becomes more abundant, so that in fine the kinetic lithio derivative is 173, whereas the thermodynamic derivative is 172. [Pg.123]

FIGURE 3 17 A guide to representing the orienta tions of the bonds in the chair conformation of cycio hexane... [Pg.118]

FIGURE 7 16 Poly mers of propene The mam chain IS shown in a zigzag conformation Every other carbon bears a methyl sub stituent and is a chirality center (a) All the methyl groups are on the same side of the carbon chain in isotactic polypropylene (b) Methyl groups alternate from one side to the other in syndiotactic polypropy lene (c) The spatial orienta tion of the methyl groups IS random in atactic polypropylene... [Pg.313]

Once formed the tetrahedral intermediate can revert to starting materials by merely reversing the reactions that formed it or it can continue onward to products In the sec ond stage of ester hydrolysis the tetrahedral intermediate dissociates to an alcohol and a carboxylic acid In step 4 of Figure 20 4 protonation of the tetrahedral intermediate at Its alkoxy oxygen gives a new oxonium ion which loses a molecule of alcohol m step 5 Along with the alcohol the protonated form of the carboxylic acid arises by dissocia tion of the tetrahedral intermediate Its deprotonation m step 6 completes the process... [Pg.851]

The halide anion of quaternary ammonium iodides may be replaced by hydroxide by treatment with an aqueous slurry of silver oxide Silver iodide precipitates and a solu tion of the quaternary ammonium hydroxide is formed... [Pg.938]

Phenol was first isolated m the early nineteenth century from coal tar and a small por tion of the more than 4 billion lb of phenol produced m the United States each year comes from this source Although significant quantities of phenol are used to prepare aspirin and dyes most of it is converted to phenolic resins used m adhesives and plastics... [Pg.999]

FIGURE 26 8 The distribu tion of the C label in citronellal biosynthesized from acetate in which the methyl carbon was isoto pically enriched with C... [Pg.1092]

FIGURE 27 12 Identifica tion of the N terminal ammo acid of a peptide by Edman degradation... [Pg.1134]

The direct synthesis in an aromatic hydrocarbon medium is patented, using a triethyl aluminum catalyst (48) in this case, crystallisa tion of the product from a solvent is not needed. [Pg.305]

The growth and commercializa tion of the nonoxide fiber market parallels the high strength composite industry. If prices for nonoxide fibers with lengths of 2—10 cm reach the 10—20/kg range, a large potential market should develop. [Pg.55]

Historically, rickets prevention or cure was used to evaluate adequate vitamin nutrient levels. More recendy, in the absence of uv light, Edwards (216) found different vitamin levels were required for the optimisa tion of the various effects of vitamin in poultry, ie, 275 lU/kg for growth, 503... [Pg.138]

The solubihty—temperature curves for the Na20—B2O2—H2O system are given in Figure 5 (Table 9). The solubiUty curves of the penta- and decahydrates intersect at 60.6—60.8°C, indicating that the decahydrate, when added to a saturated solution above this temperature, dissolves with crystallisa tion of the pentahydrate and the reverse occurs below this temperature. This transition temperature may be lowered in solutions of inorganic salts, eg, 49.3°C in solutions saturated with sodium sulfate and 39.6°C with sodium chloride. Heats of solution for borax have been determined (67,73) and the manufacturer quotes a value of about 283 kJ/kg (67.6 kcal/mol) (33). [Pg.196]

J. E. Van Stein Cahenfels and J. Van Laar, Seminar on the Economic and Technical Aspects of the Modemi tion of the Steel Industry, Krakow, Poland, May 15-19, 1989, United Nations Paper STEEL/SEM.15/R.39, Feb. 23,1989. [Pg.524]

In the preparation of commercial DGEBPA, an excess of epichl orohydrin is used in order to minimize polymeriza tion of the reactants to higher molecular-weight species. Nevertheless, the typical viscous final product usually contains ca 80% by weight of the monomeric (n = 0) DGEBPA as deterrnined by gel-permeation chromatography (gpc). The manufacture of Hquid epoxy resins in a batch process has been described in some detail (9). [Pg.365]

Catalysts such as iron oxides cause isomeriza tion of the ethylene oxide to acetaldehyde with the evolution of heat. The acetaldehyde has a much lower autoignition temperature in air than does ethylene oxide, and the two effects may lead to hot-spot ignition (190,191). [Pg.465]

Law Simplified flux equations that arise from Eqs. (5-181) and (5-182) can be used for nnidimensional, steady-state problems with binary mixtures. The boundary conditions represent the compositions and I Aft at the left-hand and right-hand sides of a hypothetical layer having thickness Az. The principal restric tion of the following equations is that the concentration and diffnsivity are assumed to be constant. As written, the flux is positive from left to right, as depic ted in Fig. 5-25. [Pg.593]

Westerterp et al. (1984 see Case Study 4, preceding) conclude, Thanks to mathematical techniques and computing aids now available, any optimization problem can be solved, provided it is reahstic and properly stated. The difficulties of optimization lie mainly in providing the pertinent data and in an adequate construc tion of the objective function. ... [Pg.706]

The reset time, which is nser-adjnstable, can range from 0.05 seconds to 80 minutes or more, depending on controller design. The reset time constant, when converted to frequency 1/2(Tr) Hz (where Tr is the reset time in seconds), determines the frequency where the reset and proportional response characteristics of the controller merge (see Fig. 8-64Z ). Tuning the reset adjustment on the controller moves the reset frequency to the left or right along the frequency axis and thereby affec ts the reset ac tion of the controller. [Pg.777]

Rapid Manufacturing-Cost Estimates Fixed manufacturing costs are a func tion of the fixed-capital investment and are independent of the production rate of the plant. Property taxes or rates depend on location. They may be taken as 2 percent of the fixed-capital cost of the plant in the absence of specific data. The cost of insurance depends on both location and the hazardous nature of the materials handled. This cost is normally of the order of 1 percent of the fixed-capital cost of the plant. [Pg.855]

Push -on joints (Fig. 10-137) require diametral control of the end of the pipe. They are used for brittle materials. Pipe, fittings, and valves are furnished with the bells cast on one or more ends. Considerable force is required to push the spigot through the O ring this is reduced by the extension on the O ring, which causes the friction of the pipe to elongate the cross sec tion of the main portion of the O ring. [Pg.958]


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See also in sourсe #XX -- [ Pg.145 ]




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