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Increasing the Complexity

Both vacuum operation and the use of refrigeration incur capital and operating cost penalties and increase the complexity of the design. They should be avoided if possible. For a first pass through... [Pg.76]

Hoffman s extended Huckel theory, EHT (Hoffman, 1963), includes all bonding orbitals in the secular matrix rather than just all n bonding orbitals. This inclusion increases the complexity of the calculations so that they are not practical without a computer. The basis set is a linear combination that includes only valence orbitals... [Pg.221]

The increased acidity of the larger polymers most likely leads to this reduction in metal ion activity through easier development of active bonding sites in siUcate polymers. Thus, it could be expected that interaction constants between metal ions and polymer sdanol sites vary as a function of time and the sihcate polymer size. The interaction of cations with a siUcate anion leads to a reduction in pH. This produces larger siUcate anions, which in turn increases the complexation of metal ions. Therefore, the metal ion distribution in an amorphous metal sihcate particle is expected to be nonhomogeneous. It is not known whether this occurs, but it is clear that metal ions and siUcates react in a complex process that is comparable to metal ion hydrolysis. The products of the reactions of soluble siUcates with metal salts in concentrated solutions at ambient temperature are considered to be complex mixtures of metal ions and/or metal hydroxides, coagulated coUoidal size siUca species, and siUca gels. [Pg.7]

Annelation increases the complexity of the spectra just as it does in the carbocyclic series, and the spectra are not unlike those of the aromatic carbocycle obtained by formally replacing the heteroatom by two aromatic carbon atoms (—CH=CH—). Although quantitatively less marked, the same trend for the longest wavelength band to undergo a bathochromic shift in the heteroatom sequence O < NH < S < Se < Te is discernible in the spectra of the benzo[Z>] heterocycles (Table 17). As might perhaps have been anticipated, the effect of the fusion of a second benzenoid ring on to these heterocycles is to reduce further the differences in their spectroscopic properties (cf. Table 18). The absorption of the benzo[c]... [Pg.14]

The permitting reqiiirements and procedures for a proposed NSR source are quite different, if the source is to be located in a nonattaiu-ment area for any of its major emitted pollutants, than if it is to be located in an attainment area. This usually increases the complexity of the permit application for such a source. [Pg.2311]

The combination of several unit operations into a single piece of equipment can eliminate equipment and simplify a process. There may be inherent safety conflicts resulting from this strategy (see Section 2.4). Combining a number of process operations into a single device increases the complexity of that device, but it also reduces the number of vessels or other pieces of equipment required for the process. Careful evaluation of the options with respect to all hazards is necessary to select the inherently safer overall option. [Pg.32]

Although it is attractive to directly convert chemical energy to electricity, PEM fuel cells face significant practical obstacles. Expensive heavy metals like platinum are typically used as catalysts to reduce energy barriers associated with the half-cell reactions. PEM fuel cells also cannot use practical hydrocarbon fuels like diesel without complicated preprocessing steps. Those significantly increase the complexity of the overall system. At this time, it appears likely that PEM fuel cells will be confined to niche applications where high cost and special fuel requirements are tolerable. [Pg.504]

Some studies of more complicated systems have been attempted but, as the number of variables increases, the complexities of interpretation and the difficulties in obtaining meaningful kinetic data become intractable. [Pg.15]

This represents a simple form of control for a single variable, though in a modem plant many parameters are controlled at the same time from various measuring instruments, and the variables on a plant such as a distillation unit are frequently linked together, thus increasing the complexity of control that is required. [Pg.232]

On the other hand, RPBs suffer from poor heat transfer possibilities. Heat input could theoretically be achieved by use of eddy currents, microwaves, or sonic energy, and thus endothermic reactions are, in principle, possible. The heat removal is more problematic and exothermic reactions must be conducted adiabatically within the rotor. Alternating packing and heat transfer plates could perhaps be an option, although it would greatly increase the complexity and the price of the reactor. [Pg.301]

From Scheme 7, the extraordinary complexity of the species that can be formed, at least in principle, during the initiation step can be appreciated. It is important to underline that the number of possible initiation mechanisms can be greater than the seven indicated in Scheme 7, because several mechanisms can be found not only coming from top to bottom in a vertical way, but also following a zig-zag path. Furthermore, most of the species reported here could be in equilibrium during the early stages of the polymerization reaction, increasing the complexity of the scenario. [Pg.25]

Using the above transformation, we are able to perform an unconstrained search over k,. For any value of k the original parameter k, remains within its limits. When k, approaches very large values (tends to infinity), k, approaches its lower limit, kmm j whereas when k, approaches very large negative values (tends to minus infinity), k, approaches its upper limit, kmax>1. Obviously, the above transformation increases the complexity of the mathematical model however, there are no constraints on the parameters. [Pg.163]

Oxidation-reduction reactions may affect the mobility of metal ions by changing the oxidation state. The environmental factors of pH and Eh (oxidation-reduction potential) strongly affect all the processes discussed above. For example, the type and number of molecular and ionic species of metals change with a change in pH (see Figures 20.5-20.7). A number of metals and nonmetals (As, Be, Cr, Cu, Fe, Ni, Se, V, Zn) are more mobile under anaerobic conditions than aerobic conditions, all other factors being equal.104 Additionally, the high salinity of deep-well injection zones increases the complexity of the equilibrium chemistry of heavy metals.106... [Pg.820]

Stan Shostak As I said, we have an understanding at various levels. We use the term levels of organization and levels of complexity or what have you, and I don t have a quarrel with data at any level whatsoever. My intention was to increase the complexity of the ideas, to ask, to... [Pg.110]

The tissue surrogates described here clearly represent a simplification of real FFPE tissues. However, they represent a useful and efficient construct for the evaluation and optimization of tissue extraction conditions for proteomic studies. More informative studies will likely be realized by using more complex tissue surrogates, which can be created by incorporating additional proteins into lysozyme solutions. Tissue surrogates comprised of up to five proteins have been successfully analyzed by MS (Fowler, unpublished data). Additionally, RNA, DNA, lipids, or carbohydrates can be added at nanomolar to millimolar concentrations to increase the complexity of the model system to better mimic whole tissue. The use of these more complex tissue surrogates should facilitate the development of protein recovery protocols optimal for proteomic investigation. [Pg.247]

In order to increase the complexity of the peripheral epitopes resulting from the self-assembly process, glycodendrons have been successfully grafted onto various ligands, allowing the formation of dense glycocomplexes. Indeed, in most of the examples, branching of the dendrimers produces a microenvironment that... [Pg.274]

Including electronic interactions increases the complexity of the problem enormously, such that the number of atoms to be included typically ranges from 10-100, depending on the methodology chosen. The more accurate the treatment, the more computationally costly the calculation will be. This implies that quantum chemical calculations are generally performed on small model systems, usually in a vacuum or surrounded by a dielectric continuum that mimics bulk solution effects. Based on studies of, e.g., several alternative reaction mechanisms or properties of different... [Pg.113]


See other pages where Increasing the Complexity is mentioned: [Pg.383]    [Pg.1]    [Pg.457]    [Pg.317]    [Pg.233]    [Pg.294]    [Pg.93]    [Pg.1083]    [Pg.301]    [Pg.144]    [Pg.139]    [Pg.244]    [Pg.57]    [Pg.526]    [Pg.258]    [Pg.1083]    [Pg.847]    [Pg.5]    [Pg.49]    [Pg.592]    [Pg.796]    [Pg.409]    [Pg.409]    [Pg.230]    [Pg.203]    [Pg.180]    [Pg.197]    [Pg.227]    [Pg.94]    [Pg.117]    [Pg.179]    [Pg.79]    [Pg.31]   


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