Efficiency utilization of theoretical

This is a useful expression, since it provides a comparison of experimental performance against what might be expected theoretically. This can provide a measure of coating quality, or utilization of theoretical efficiency, %UTE. For a uniform, thin film coating, %UTE might be expected to be high (e.g., 80%). For a difficult to coat phase, a lower coating efficiency may be accepted for preparation of a capillary column. 

This parameter, also called the utilization of theoretical efficiency (UTE), is the ratio of the actual efficiency of a capillary column to its theoretical maximum possible efficiency. Coating efficiency or UTE is expressed as... 

This relationship, although it neglects the influence of the stationary phase on band broadening, is clearly reflected in the experimental data, where smaller inner diameters produce lower minimum plate heights. The last column of Table 4.2 lists the utilization of theoretical efficiency (UTE%) for each column at its... 

The atom utilization or atom efficiency concept is a useful tool for rapid evaluation of the amount of waste that will be generated by alternative routes to a particular product. It is calculated by dividing the molecular weight of the desired product by the sum total of the molecular weights of all the substances produced in the stoichiometric equation of the reaction(s) in question. The comparison is made on a theoretical (i.e. 100% chemical yield) basis. Fig. 2.8 shows a simple illu.stration of the concept for ethylene oxide manufacture. 

The use of the Poisson distribution for this purpose predates the statistical overlap theory of Davis and Giddings (1983), which also utilized this approach, by 9 years. Connors work seems to be largely forgotten because it is based on 2DTLC that doesn t have the resolving power (i.e., efficiency or the number of theoretical plates) needed for complex bioseparations. However, Martin et al. (1986) offered a more modem and rigorous theoretical approach to this problem that was further clarified recently (Davis and Blumberg, 2005) with computer simulation techniques. Clearly, the concept and mathematical approach used by Connors were established ahead of its time. 

The catalytic RCM and kinetic resolution can be carried out in a single vessel as well. This is particularly important for the practical utility of the Zr-catalyzed resolution Because the best theoretical yield in a classical resolution is 50%, it is imperative that the racemic substrate is prepared readily (or 50% material loss will be too costly). In this instance, the racemic substrate is not only obtained efficiently, it is synthesized in a catalytic manner and need not even be isolated prior to the resolution. Two representative examples are illustrated in Scheme 4 [5a]. The tandem catalytic RCM, leading to rac-19 and its subsequent catalytic resolution proceeds with excellent efficiency the one-vessel, two-stage process... 

Need for more theoretical or experimental information on the "efficiency p" of utilization of macroscopic dissipated power P at the molecular scale (e). 

The utility of the concept of aerosol particle electrical drift velocity can be shown by using it to estimate the theoretical efficiency of an electrostatic precipitator. For simplicity it is assumed that the collector is cylindrical, having a radius R (although this assumption does not affect the results), and that an aerosol is uniformly distributed across the entrance of the collector. In addition, turbulent flow in the collector is assumed such that the uncollected aerosol remains uniformly distributed at any distance from the entrance of the tube. If the electrical drift velocity is constant, the chance of a particle 4> being collected in a time At is... 

The urgent need to develop more efficient fuel cell anodes and cathodes has brought the electrochemical, catalytic, and surface science communities closer than ever before and has made electrocatalysis a rapidly growing field both in experimental new findings and in theoretical understanding. It is very likely that the rapid advances in catalyst and electrocatalyst nanoparticle preparation and characterization [10], together with the utilization of new powerful in situ techniques, such as electrochemical nuclear magnetic resonance (NMR) [216] in conjunction with... 

Open-tubular columns utilized In gas chromatography have, with few exceptions, been of 0.2 mm diameter or larger and have therefore provided at most only a few thousand effective theoretical plates per meter length. Nevertheless, the theoretical background for design of column efficiencies of 10 or more effective plates per meter was presented as early as 1958. Laub et (19) have explored the practical limits of the early theoretical work and in particular, the fabrication and properties of capillary columns of Inner diameter ranging from 0.3 to 0.035 mm. The latter exhibits on the order of 2 x 10 N j /m for k of 17. Much higher efficiencies could be realized with the mass spectrometrlc detector. 

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