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True minimum

Thus, if film transfer coefficients vary significantly, then Eq. (7.6) does not predict the true minimum network area. The true minimum area must be predicted using linear programming. However, Eq. (7.6) is still a useful basis to calculate the network area for the purposes of capital cost estimation for the following reasons ... [Pg.219]

Information about critical points on the PES is useful in building up a picture of what is important in a particular reaction. In some cases, usually themially activated processes, it may even be enough to describe the mechanism behind a reaction. However, for many real systems dynamical effects will be important, and the MEP may be misleading. This is particularly true in non-adiabatic systems, where quantum mechanical effects play a large role. For example, the spread of energies in an excited wavepacket may mean that the system finds an intersection away from the minimum energy point, and crosses there. It is for this reason that molecular dynamics is also required for a full characterization of the system of interest. [Pg.254]

A steepest descents minimisation algorithm produces a path that oscillates about the true reaction pathway Ihe transition structure to a minimum. [Pg.304]

At larger bond lengths, the true potential is "softer" than the harmonie potential, and eventually reaehes its asymptote whieh lies at the dissoeiation energy Dg above its minimum. This negative deviation of the true V(R) from 1/2 k(R-Rg)2 eauses the true vibrational energy levels to lie below the harmonie predietions. [Pg.358]

In order to define how the nuclei move as a reaction progresses from reactants to transition structure to products, one must choose a definition of how a reaction occurs. There are two such definitions in common use. One definition is the minimum energy path (MEP), which defines a reaction coordinate in which the absolute minimum amount of energy is necessary to reach each point on the coordinate. A second definition is a dynamical description of how molecules undergo intramolecular vibrational redistribution until the vibrational motion occurs in a direction that leads to a reaction. The MEP definition is an intuitive description of the reaction steps. The dynamical description more closely describes the true behavior molecules as seen with femtosecond spectroscopy. [Pg.159]

This technique is available only for the MM-t force field. As is true for the conjugate gradient methods, you should not use this algorithm when the initial interatomic forces are very large (meaning, the molecular structure is far from a minimum). [Pg.60]

It may be possible for a company to negotiate the purchase of a material at a cost per unit that is significantly lower than the current pubhshed price. This is particularly true if large quantities are involved. Thus, estimates should be presented for both minimum and maximum costs. Price trends, availabihty, and quality are other factors that should be considered. A knowledge of price trends is particularly important for a product that a company may not manufacture for sever years. [Pg.855]

Equation (10-2) is true only for pipelines of relatively short lengths since otherwise the longitudinal resistance will be noticeable at longer distances. Thus in Eq. (10-2) / E will approach Z, not zero, for a long length. Here Z denotes the characteristic resistance defined in Eq. (24-66). Z is therefore the minimum grounding resistance for the case where current is fed at one end of the pipeline. This quantity is reduced by half for current fed in at a central point on the pipe. It follows from Eq. (24-66)... [Pg.266]

Note from Fig. 2.20 that although the true position of the boron KLL Auger peak in the N(E) spectrum is at 167 eV, the position in the dN(E)/dE spectrum is taken for purely conventional reasons to be that of the negative minimum, i.e. at 175 eV. [Pg.36]

Equations (4) and (5) predict that the optimum linear velocity should be linearly related to the diffusivity of the solute in the mobile phase, whereas the minimum value of the HETP should be constant and independent of the solute diffusivity. This, of course, will only be true for solutes eluted at the same (k ). It is seen, from Table 1, that (by appropriate adjustment of the concentration of ethyl acetate) the values of both (k ) and (k e) have been kept approximately constant for all the mobile phase... [Pg.326]

Thus, the user can input the minimum site boundary distance as the minimum distance for calculation and obtain a concentration estimate at the site boundary and beyond, while ignoring distances less than the site boundary. If the automated distance array is used, then the SCREEN model will use an iteration routine to determine the maximum value and associated distance to the nearest meter. If the minimum and maximum distances entered do not encompass the true maximum concentration, then the maximum value calculated by SCREEN may not be the true maximum. Therefore, it is recommended that the maximum distance be set sufficiently large initially to ensure that the maximum concentration is found. This distance will depend on the source, and some trial and error may be necessary however, the user can input a distance of 50,000 m to examine the entire array. The iteration routine stops after 50 iterations and prints out a message if the maximum is not found. Also, since there may be several local maxima in the concentration distribution associated with different wind speeds, it is possible that SCREEN will not identify the overall maximum in its iteration. This is not likely to be a frequent occurrence, but will be more likely for stability classes C and D due to the larger number of wind speeds examined. [Pg.306]

By constructing a pinch diagram for the problem, find the minimum cost of MSAs needed to remove phenol from Rg and R2. How do you characterize the point at which both composite streams touch Is it a true pinch point ... [Pg.77]


See other pages where True minimum is mentioned: [Pg.211]    [Pg.302]    [Pg.211]    [Pg.302]    [Pg.218]    [Pg.219]    [Pg.232]    [Pg.387]    [Pg.441]    [Pg.21]    [Pg.2350]    [Pg.264]    [Pg.72]    [Pg.147]    [Pg.189]    [Pg.284]    [Pg.291]    [Pg.304]    [Pg.499]    [Pg.97]    [Pg.1054]    [Pg.1964]    [Pg.154]    [Pg.41]    [Pg.333]    [Pg.83]    [Pg.9]    [Pg.129]    [Pg.357]    [Pg.264]    [Pg.306]    [Pg.28]    [Pg.1131]    [Pg.310]    [Pg.637]    [Pg.355]    [Pg.363]    [Pg.52]    [Pg.335]    [Pg.73]    [Pg.687]   


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Identification of True Minima

True

True minimum Subject

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