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Feasible overlapping

It is important to note that shifting the curves vertically does not alter the horizontal overlap between the curves. It therefore does not alter the amount by which the cold composite curve extends beyond the start of the hot composite curve at the hot end of the problem and the amount by which the hot composite curve extends beyond the start of the cold composite curve at the cold end. The shift simply removes the problem of ensuring temperature feasibility within temperature intervals. [Pg.175]

The perturbation theory described in section Al.5.2,1 fails completely at short range. One reason for the failure is that the multipole expansion breaks down, but this is not a fiindamental limitation because it is feasible to construct a non-expanded , long-range, perturbation theory which does not use the multipole expansion [6], A more profound reason for the failure is that the polarization approximation of zero overlap is no longer valid at short range. [Pg.195]

Safety is thus the result of multiple barriers operating in concert. Whereas each approach individually may have limitations, use in an integrated manner provides overlapping and complementary levels of protection. These approaches may provide an effective method of overcoming risk and represent the only feasible approach in the face of theoretical risks which cannot be adequately characterized by classical technology. [Pg.143]

This value corresponds to a corresponding y-scale composition of 0.0012, which is less than the supply mass fmction of phenol in either waste stream as well as the pinch composition. Hence, it is thermodynamically feasible for Sf to recover phenol from R] and R2. In addition, miy amount of phenol removed by S5 does not overlap with the load handled by the process MSAs. Therefore, the operating cost of air needed to remove 1 kg of phenol can be evaluated as follows ... [Pg.67]

The Hg-Hg bond in Hg2 + may be ascribed to overlap of the 6s orbitals with little involvement of 6p orbitals or of the filled d ° shell of each atom. If this is regarded as the coordination of Hg to an Hg + cation, the coordination of a second Hg ligand is also feasible. Accordingly, Hg3(AlCl4)2 can be obtained from a molten mixture of HgCH, Hg and AICI3 and contains the discrete, virtually linear cation... [Pg.1214]

Approximate equipment sizing. There are many combinations of equipment units that meet the requirements concerning the functions of all equipment units and the time horizons for all products. Based on the Flatz (1980) concept, a simple procedure is presented to determine feasible equipment sizes that meet all requirements for plants operated in a single-product campaign mode (no process overlapping). The procedure is illustrated in Fig. 7.4-10. [Pg.490]

Below, the procedure for the determination of dominant campaigns in a version that was proposed by Lazaro et al. (1989) is outlined. Their methodology includes enumeration of feasible production sequences, selection of dominant production lines, task sequencing, and search for an optimum with constraints. All possible production variants are generated by an enumeration procedure that takes into account the possibility of available equipment working in parallel, initial and final task overlapping, and instability of intermediate products. Non-feasible sequences are eliminated so that only favourable candidates are subjected to full evaluation. Dominant production lines are selected by maximizing the criterion ... [Pg.506]

Catalytic dehydrogenation of alcohol is an important process for the production of aldehyde and ketone (1). The majority of these dehydrogenation processes occur at the hquid-metal interface. The liquid phase catalytic reaction presents a challenge for identifying reaction intermediates and reaction pathways due to the strong overlapping infrared absorption of the solvent molecules. The objective of this study is to explore the feasibility of photocatalytic alcohol dehydrogenation. [Pg.405]

Most hydraulic fluid preparations start as chemical mixtures. For instance, there is a considerable area of overlap in the specific petroleum hydrocarbon chemicals contained in the mineral oil and polyalphaolefin hydraulic fluids. For all classes of hydraulic fluids, there may be similarities with other original products intended for use as lubricants. The complications involved in documenting the environmental fate of mixtures increase under conditions encountered at many NPL sites, where it may be hard to determine the precise original product associated with chemicals identified at an area in need of remediation. In most instances, available peer-reviewed literature, supplemented with data obtained from manufacturers of particular formulations and information in trade magazines, can supply information about the original hydraulic fluid preparations. At NPL sites, site-specific evaluations of specific chemicals may be the only feasible way to address concerns over environmental fate and potential exposure risks. [Pg.313]

For the stripping and rectifying sections to become a feasible column, the two operation leaves must overlap. Figure 12.20 shows the system chloroform, benzene and acetone. The operation leaf for a distillate composition D intersects with the operation leaf for a bottoms composition... [Pg.245]

Figure 12.20 Overlap of column section operating leaves is a necessary condition for feasible separation. (From Castillo F, Thong DY-C, Towler GP, 1998, hid Eng Chem Res, 37 987 reproduced by permission of the American Chemical Society). Figure 12.20 Overlap of column section operating leaves is a necessary condition for feasible separation. (From Castillo F, Thong DY-C, Towler GP, 1998, hid Eng Chem Res, 37 987 reproduced by permission of the American Chemical Society).
In cycloadditions two components are commonly involved, and the feasibility of a concerted process will be determined by whether overlap can take place between the HOMO of one component and the LUMO of the other. Thus for a diene plus a monoene,... [Pg.348]

To apply the rule we first draw the orbital picture of the reactants and show a geometrically feasible way to achieve overlap. Then the (4q + 2) suprafacial electrons and 4r antarafacial electrons of the components is counted. If the total is an odd number, the reaction is thermally allowed. Let us take the hypothetical cycloaddition of ethene to give cyclobutane. [Pg.34]

Fig. 5 Contour plots showing the alignment of gramicidin S in DMPC membranes at high peptidedipid ratios (>1 40), evaluated in terms of the peptide tilt angle x and its azimuthal rotation p. Feasible solutions from F-NMR of GS-3/3 (A) and GS-1/1 (B) are shown, together with additional N-NMR constraints from GS-3/3 (C) and GS-1/1 (D). A unique overlap is obtained at t 80° and p -45°, as indicated by the shaded dots... Fig. 5 Contour plots showing the alignment of gramicidin S in DMPC membranes at high peptidedipid ratios (>1 40), evaluated in terms of the peptide tilt angle x and its azimuthal rotation p. Feasible solutions from F-NMR of GS-3/3 (A) and GS-1/1 (B) are shown, together with additional N-NMR constraints from GS-3/3 (C) and GS-1/1 (D). A unique overlap is obtained at t 80° and p -45°, as indicated by the shaded dots...
For the points pictorial quality , reduction of complexity , structuring of perception , motivation , creation of a group identity , co-ordination and synchronisation , relation to feasibility and preferred instruments and typical ideal solutions , numerous interesting overlaps occur between guiding principles and Thomas Kuhn s concept of paradigms (cf Kuhn 1975). [Pg.123]

In actual in-situ coal gasification, numerous processes, i.e. oxidation, reduction, thermal cracking and a variety of catalytic as well as non-catalytic reactions, occur in overlapping zones, and to explore the chemistry of these reactions as single or consecutive unit processes is virtually impossible. It is, however, feasible to study the individual reactions under controlled conditions by simulating in-situ gasification in the laboratory. [Pg.95]

Suberized Cell Walls. An analogous set of CPMAS experiments is presented for suberin in Figure 6. Because this polymer is an integral part of the plant cell wall, the 13C NMR spectrum had contributions from both polysaccharide and polyester components. Chemical-shift assignments, summarized in Table IV, demonstrated the feasibility of identifying major polyester and sugar moieties despite serious spectral overlap. Semiquantitative estimates for the various carbon types indicated that, as compared with cutin, the suberin polyester had dramatically fewer aliphatic and more aromatic residues. A similar observation was made previously for the soluble depolymerization products of these plant polymers (1,8,11). [Pg.223]

In a move in the opposite direction, the overlaps resulting from concatenation of different polarization transfer mechanisms in combined 2D experiments can be eliminated by reducing the dimensionality of an experiment. Similarly to the successful transformation of basic 2D NMR techniques into their ID counterparts [32-34], a conversion of combined 2D NMR techniques into their ID analogs is feasible and has been explored by several groups [35-40]. From a different perspective this process can be seen as a twofold reduction of the dimensionality in a 3D experiment. Equally, concatenation of three polarization transfer steps in a single ID experiment represents transformation of a possible 4D homonuclear experiment into its ID analog. [Pg.54]


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