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Minimum Number of Cycles

The minimum number of cycles is given by the nullity or Frerejacque number ( ) according to Eq. (5). It is the difference between the number of nodes a = atoms) and the number of edges h = bonds). The value of 1 stands for the number of compounds considered (here, one compound). This minimum number corresponds to the munber of chords. These are defined as nodes that turn a cyclic graph or structure into an acyclic one. [Pg.55]


List scheduling, with operations ranked according to their urgency (the minimum number of cycles required between the operation and any enclosing timing constraints). [Pg.48]

Overlapping PGR assembly is a parallel process, by which the lengths of the overlapping oligonucleotides are extended after each PGR cycle. The theoretical minimum number of cycles (x ) needed in order to construct a double-stranded (ds)DNA molecule of the length (L) from an uniform oligonucleotide length ( ) and... [Pg.229]

An important descriptor of a chain reaction is the kinetic chain length, ie, the number of cycles of the propagation steps (eqs. 2 and 3) for each new radical introduced into the system. The chain length for a hydroperoxide reaction is given by equation (10) where HPE = efficiency to hydroperoxide, %, and 2/ = number of effective radicals generated per mol of hydroperoxide decomposed. For 100% radical generation efficiency, / = 1. For 90% efficiency to hydroperoxide, the minimum chain length (/ = 1) is 14. [Pg.335]

Generahzed correlations are available for each of the operations which make up the full filter cycle. This means that simulated operating conditions can be varied to obtain a maximum of information without requiring an excessive number of test runs. The minimum number of test runs required for a given feed will, of course, vary with the expertise of the experimenter and the number of operations performed during the filter cycle. If, for example, the operation invdves only the dewatering of a slurry which forms a cake of relatively low to moderate porosity, frequently sufficient data can be obtained in as little as six runs. For more difficult tests, more runs are usually advisable, and the novice certainly should make a larger number of runs as there is likely to be more data scatter. [Pg.1696]

In practical applications, it can be a factor that the above approach by virtue of the cycle over A values has a higher minimum number of scans per ti value than the standard experiment and its various accordion versions. For dilute samples, this does not matter but for concentrated samples the instrument time can be longer than required considering the inherent sensitivity. [Pg.320]

In the new vision, assay cycle time is dramatically reduced and the criteria used to measure assay acceptability are matched to sample type. Early screening samples may be assayed using simple methods and minimum numbers of standards. Samples from early preclinical PK studies in rats and other species may require additional standards. Finally, for PK studies performed in the lead characterization phase, one might add quality control (QC) samples. One set of rules for non-GLP assays has been codified in a recent publication.16 These rules make it possible to match the assay cycle time with the in-life cycle time in order to minimize the total discovery cycle time. [Pg.207]

The minimum value for/is 0.15, which results in an allowable displacement stress range, SA, for an indefinitely large number of cycles. [Pg.90]

Mathematically, all this iirformation is used to calculate the best fit of the model to the experimental data. Two techniques are currently used, least squares and maximum hkelihood. Least-squares refinement is the same mathematical approach that is used to fit the best line through a number of points, so that the sum of the squares of the deviations from the line is at a minimum. Maximum likelihood is a more general approach that is the more common approach currently used. This method is based on the probability function that a certain model is correct for a given set of observations. This is done for each reflection, and the probabilities are then combined into a joint probability for the entire set of reflections. Both these approaches are performed over a number of cycles until the changes in the parameters become small. The refinement has then converged to a final set of parameters. [Pg.465]

Fig. 14.9 Individual components of multidimensional optimization. This approach requires experimental compound profiling against key properties, which should be done on a designed compound subset to maximize information with a minimum number of molecules. These data are used to derive models for key properties, which are applied during the next design cycle. The results then led to augmented models. The process is characterized by a tight integration of in vitro and in silico tools for profiling compound series to guide chemical optimization. Fig. 14.9 Individual components of multidimensional optimization. This approach requires experimental compound profiling against key properties, which should be done on a designed compound subset to maximize information with a minimum number of molecules. These data are used to derive models for key properties, which are applied during the next design cycle. The results then led to augmented models. The process is characterized by a tight integration of in vitro and in silico tools for profiling compound series to guide chemical optimization.
The model includes fundamental hydrocarbon conversion kinetics developed on fresh catalysts (referred to as start-of-cycle kinetics) and also the fundamental relationships that modify the fresh-catalyst kinetics to account for the complex effects of catalyst aging (deactivation kinetics). The successful development of this model was accomplished by reducing the problem complexity. The key was to properly define lumped chemical species and a minimum number of chemical reaction pathways between these lumps. A thorough understanding of the chemistry, thermodynamics, and catalyst... [Pg.193]

Resampling with the Same Resin. Resin cleaning was performed to produce the minimum number of GC-FID responses from the cleaning solvent. One cycle of exposure to a sample of water followed by elution of the columns caused the reappearance of the characteristic contaminants, which have been tentatively identified by GC-MS as methyl benzoate, C2-benzaldehyde, C2-acetophenone, and the unknown listed in Table II and shown in Figures 4 and 5. A similar phenomenon also has been reported by Bean et al. (16) and Care et al. (22). [Pg.287]

Reactor core fuel -type - enrichment by 235U, %, maximum -average burn-up, MWday/kg -fuel cycle, eff. days, minimum - number of refuellings Based on UO2 w/multi-layer coatings 20 125 900 3... [Pg.71]

Click on Calculate. Energy minimization with the N-C-C-N torsion constrained initially at 60°, then at 55° and so on will begin. The results will appear in tabular and graphical forms in windows as shown in Fig. 17.15.5 and 17.15.6. If there are asterisks in the Minimum not reached column increase the number of cycles in the optimization controls and repeat the calculations. [Pg.265]

In an industrial hydroformylation reaction with a rhodium catalyst in the presence of excess phosphine and high pressures of CO, what would probably be the minimum number of catalytic cycles and intermediates ... [Pg.101]

All possible interactions between the K and L groups were taken into account and Akk = 0. The definition contains a minimum number of groups and is satisfactory for most of the binary systems studied. However, it cannot take into account the structural differences which exist between position isomers. This is the case of polycyclic aromatic compounds presenting cycle position isomers or substitute position isomers. Structural differences of this type determine the gaps between the values of certain thermophysical properties of isomers, such as, for example, the fusion temperature or sublimation enthalpy. The further the temperature falls, the more these differences are accentuated. The representation of the solid-fluid (low temperature) equilibria is consequently more difficult and the model must take into account the existing structural differences. We came across this problem in the compounds such as anthracene, phenanthrene, pyrene, methylated naphthalenes, hexamethylbenzene and triphenylmethane. As it was out of the question to increase the number of groups because... [Pg.472]


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