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Simplifications in

The general problem simplifies considerably in the finite field. F[2. Because circuits are always counted at least twice, their number contributes a factor = 0 (mod 2) we see from equation (5.14), therefore, that the only structural information necessary to obtain Pi x) is that of the parity of disjoint edge distributions. Moreover, since there is no way to distribute disjoint edges among an odd number of vertices, equation (5.13) gives [Pg.269]

we give a sampling of the sorts of dynamical behaviors that can immediately be deduced from basic topological features of . [Pg.269]

Reversible Behavior all states E are on cycles if and only x does not divide Pl x), a fact requiring only that the last coefficient a v = 1 (mod 2). We conclude that [Pg.269]

there are no with reversible dynamics under OT rules for odd N. [Pg.269]

for N — 2j we can have reversible behavior if and only if the number of j-disjoint edges in is odd. The topological content of reversible dynamics is [Pg.269]


If only zero-order states from the same polyad are conpled together, this constitutes a fantastic simplification in the Flamiltonian. Enonnons compntational economies result in fitting spectra, becanse the spectroscopic Flamiltonian is block diagonal in the polyad nnmber. That is, only zero-order states within blocks with the same polyad number are coupled the resulting small matrix diagonalization problem is vastly simpler than diagonalizing a matrix with all the zero-order states conpled to each other. [Pg.66]

Recognized trivial names for composite radicals are used if they lead to simplifications in naming. Examples are... [Pg.11]

A second common approximation is the steady-state condition. That arises in the example if /fy is fast compared with kj in which case [i] remains very small at all times. If [i] is small then d[I] /dt is likely to be approximately zero at all times, and this condition is commonly invoked as a mnemonic in deriving the differential rate equations. The necessary condition is actually somewhat weaker (9). Eor equations 22a and b, the steady-state approximation leads, despite its different origin, to the same simplification in the differential equations as the pre-equihbrium condition, namely, equations 24a and b. [Pg.514]

Molecular Connectivity Indexes and Graph Theory. Perhaps the chief obstacle to developing a general theory for quantification of physical properties is not so much in the understanding of the underlying physical laws, but rather the inabiUty to solve the requisite equations. The plethora of assumptions and simplifications in the statistical mechanics and group contribution sections of this article provide examples of this. Computational procedures are simplified when the number of parameters used to describe the saUent features of a problem is reduced. Because many properties of molecules correlate well with stmctures, parameters have been developed which grossly quantify molecular stmctural characteristics. These parameters, or coimectivity indexes, are usually based on the numbers and orientations of atoms and bonds in the molecule. [Pg.255]

Presented in Table 1 is a list of the parameters in Eqs. (2) and (3) and the type of target data used for their optimization. The infonnation in Table 1 is separated into categories associated with those parameters. It should be noted that separation into the different categories represents a simplification in practice there is extensive correlation between the different parameters, as discussed above for example, changes in bond parameters that affect the geometry may also have an influence on AGsoivation for a given model compound. These correlations require that parameter optimization protocols include iterative approaches, as will be discussed below. [Pg.18]

Retrosynthetic analysis can often be enhanced by strategies built around tactical combinations of PG-keyed transforms which together produce molecular simplification in a coordinated (but subtle) way. The concept of tactical combinations of transforms and a few examples of such combinations have been described in Section 2.10. The use of FG-keyed tactical combinations may be illustrated by a selection of specific applications. [Pg.62]

It should be observed that every element except the powder system in the recovery system is chosen for favorable shock properties which can be confidently simulated numerically. The precise sample assembly procedures assure that the conditions calculated in the numerical simulations are actually achieved in the experiments. The influence of various powder compacts in influencing the shock pressure and mean-bulk temperature must be determined in computer experiments in which various material descriptions are used. Fortunately, the large porosity (densities from 35% to 75% of solid density) leads to a great simplification in that the various porous samples respond in the same manner due to the radial loading introduced from the porous inclusion in the copper capsule. [Pg.153]

In conclusion, classical lamination theory enables us to calculate forces and moments if we know the strains and curvatures of the middle surface (or vice versa). Then, we can calculate the laminae stresses in laminate coordinates. Next, we can transform the laminae stresses from laminate coordinates to lamina principal material directions. Finally, we would expect to apply a failure criterion to each lamina in its own principal material directions. This process seems straightfonward in principle, but the force-strain-curvature and moment-strain-curvature relations in Equations (4.22) and (4.23) are difficult to completely understand. Thus, we attempt some simplifications in the next section in order to enhance our understanding of classical lamination theory. [Pg.202]

The calculations that have been carried out [56] indicate that the approximations discussed above lead to very good thermodynamic functions overall and a remarkably accurate critical point and coexistence curve. The critical density and temperature predicted by the theory agree with the simulation results to about 0.6%. Of course, dealing with the Yukawa potential allows certain analytical simplifications in implementing this approach. However, a similar approach can be applied to other similar potentials that consist of a hard core with an attractive tail. It should also be pointed out that the idea of using the requirement of self-consistency to yield a closed theory is pertinent not only to the realm of simple fluids, but also has proved to be a powerful tool in the study of a system of spins with continuous symmetry [57,58] and of a site-diluted or random-field Ising model [59,60]. [Pg.150]

A simplification in the graphical interpretation of acyclic chemical compounds is possible in the case of saturated acyclic hydrocarbons, once known as paraffins but now more usually called "alkanes". These have the general formula indicating the... [Pg.105]

This equation reduces to Equation 6.8 upon simplification. In terms of agonist response, Equation 6.8 becomes... [Pg.102]

The adjacent iodine and lactone groupings in 16 constitute the structural prerequisite, or retron, for the iodolactonization transform.15 It was anticipated that the action of iodine on unsaturated carboxylic acid 17 would induce iodolactonization16 to give iodo-lactone 16. The cis C20-C21 double bond in 17 provides a convenient opportunity for molecular simplification. In the synthetic direction, a Wittig reaction17 between the nonstabilized phosphorous ylide derived from 19 and aldehyde 18 could result in the formation of cis alkene 17. Enantiomerically pure (/ )-citronellic acid (20) and (+)-/ -hydroxyisobutyric acid (11) are readily available sources of chirality that could be converted in a straightforward manner into optically active building blocks 18 and 19, respectively. [Pg.235]

In addition to looking for simple relationships that may exist between the burn-out flux and the system-describing parameters, the possibility also exists of trying to find a simplification in the form of a contraction in the number... [Pg.238]

The kinetic information is obtained by monitoring over time a property, such as absorbance or conductivity, that can be related to the incremental change in concentration. The experiment is designed so that the shift from one equilibrium position to another is not very large. On the one hand, the small size of the concentration adjustment requires sensitive detection. On the other, it produces a significant simplification in the mathematics, in that the re-equilibration of a single-step reaction will follow first-order kinetics regardless of the form of the kinetic equation. We shall shortly examine the data workup for this and for more complex kinetic schemes. [Pg.256]

Most of the enzymes are built of homo or heteromultimeric structures. For the sake of simplification, in the figures only the structures of the monomeric unit of the homomultimer will be shown. [Pg.362]

Sensitivity to step size was thought to be likely due to an unnecessary simplification in the original development of the model. The simplification was to consider initiator concentration constant over a small time increment. When instead the initiator was allowed to vary according to the usual first order decomposition path an analytical solution for the variation of polymer concentration could still readily be obtained and was as follows ... [Pg.512]

The fact that the fuel/air ratio is spatially constant in HCSI engines, at least within a reasonably close approximation, allows substantial simplifications in combustion models. The burn rate or fuel consumption rate dm /dt is expressed as a function of flame surface area the density of the unburnt fuel/air mixture Pu, the laminar burning velocity Sl, and the fluctuations of velocities, i.e., E as a measure of turbulence, u. ... [Pg.180]

Greatest simplification (in middle of molecule, at branchpoint, rings from chains. [Pg.100]

Figure 3 demonstrates the simplifications in the spectrum of an optimized laser pulse that can be achieved through the application of the sifting technique [see Fq. (7)]. The excitation efficiency of the pulse is only minimally reduced due to the additional restrictions imposed in the sifting procedure. The example used in this case is for a vibrational-rotational excitation process, H2(v = 0,7 = 0) H2(v =1,/ = 2). [Pg.62]

Some of the elements of thermodynamics of irreversible processes were described in Sections 2.1 and 2.3. Consider the system represented by n fluxes of thermodynamic quantities and n driving forces it follows from Eqs (2.1.3) and (2.1.4) that n(n +1) independent experiments are needed for determination of all phenomenological coefficients (e.g. by gradual elimination of all the driving forces except one, by gradual elimination of all the fluxes except one, etc.). Suitable selection of the driving forces restricted by relationship (2.3.4) leads to considerable simplification in the determination of the phenomenological coefficients and thus to a complete description of the transport process. [Pg.431]

Alclofenac (26) represents one of the more extreme simplifications in this class of antiinflammatory agents. The general method for prepara-... [Pg.68]

Han and Griffith (1965a) developed a modified version of an ebullition cycle and, using a simplification in the temperature profile equation, they obtained an explicit form for the waiting period ... [Pg.50]


See other pages where Simplifications in is mentioned: [Pg.2200]    [Pg.570]    [Pg.143]    [Pg.150]    [Pg.189]    [Pg.19]    [Pg.65]    [Pg.9]    [Pg.51]    [Pg.47]    [Pg.32]    [Pg.269]    [Pg.14]    [Pg.222]    [Pg.288]    [Pg.150]    [Pg.101]    [Pg.237]    [Pg.593]    [Pg.269]    [Pg.186]    [Pg.141]    [Pg.18]    [Pg.769]    [Pg.284]    [Pg.363]    [Pg.455]   


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