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Recalculation procedure

Figure 6.3 presents the time variations for the same correlation function as in Fig. 6.2, but those obtained from the abovementioned recalculation procedure are performed at 250 time integration steps. It is clear that this recalculation procedure extends the applicability of the present semiclassical method to an arbitrarily long propagation duration. [Pg.130]

The computational cost of this recalculation procedure is roughly the same as that of the direct double summation with respect to the trajectories. If the propagation duration is long, the re-expansion should be performed every 200 300 time integration step. This means that this new algorithm can reduce the computational cost of semiclassical calculations by more than two orders of magnitude in comparison with the direct implementation of semiclassical methods into the OCT. [Pg.130]

Table 4.6 Demonstration of the external standard method recalculation procedure to obtain XRD QPA results... Table 4.6 Demonstration of the external standard method recalculation procedure to obtain XRD QPA results...
In some cases, reported data do not satisfy a consistency check, but these may be the only available data. In that case, it may be possible to smooth the data in order to obtain a set of partial molar quantities that is thermodynamically consistent. The procedure is simply to reconstmct the total molar property by a weighted mole fraction average of the n measured partial molar values and then recalculate normalised partial molar quantities. The new set should always be consistent. [Pg.236]

At this step in the design procedure, it is necessary to consider the type of contaminant emission that the booth is designed to control. With the above assumption of influx velocity (0.1 to 0.2 m s ), all emitted material should remain in the booth. With these velocities, it will not be possible to draw in any contaminants that escape the booth. In case of doubt, the influx velocity, zv , should be increased and the necessary hood flow rate should be recalculated. [Pg.884]

The procedure for recalculating the HI by effect and by mechanism of action is briefly described later. If one of the effect-specific luizard indices exceeds unity, consideration of tlic mechanism of action might be warranted. A strong case is required, however, to indicate that two compounds which produce adverse effects on the same organ system (c.g., liver), altliough by different mechanisms, should not be treated as dose additive. Any such determination should be reviewed. [Pg.401]

In the Direct SCF method, we do. not store the two-electron integrals over the basis functions, we recalculate them on demand every cycle of the HF procedure At first sight, this may seem wasteful, but Conventional methods rely on disk input/output transfer rates whilst Direct methods rely on processor power. There is obviously a balance between processor speed and disk I/O. Just for the record my calculation on aspirin (73 basis functions) took 363 s using the Direct method and 567 s using the Conventional method. [Pg.180]

If the original macromolecular density matrix is already available, then such approximate macromolecular electron densities for slightly distorted nuclear geometries are simpler to calculate than the full recalculation of an ADMA macromolecular density matrix that involves a new fragmentation procedure. [Pg.76]

Where the calculation of the net present value was straightforward, die determination of the rate of return requires a trial-and-error procedure. An interest rate is chosen and then the net present value is determined. If it is not zero, another interest rate is chosen and the net present value is recalculated. This is continued until a zero net present value is obtained. [Pg.311]

I calculated all of the yps using the current values of y. These are the elements in the last column of sleq. Then I incremented the first dependent variable y(i) by a small amount, yinc, and recalculated all of the yps. I subtracted the new values from the original values and divided the difference by yinc. These are the elements for the first column of the sleq array. I restored y(l) to its original value and repeated the procedure with y(2) to get the elements for the second column. I did this until all the columns had been evaluated. Finally, I added IIdelx to the diagonal elements. These procedures yielded values of the elements of the sleq array that are identical to those calculated with the linearized algebraic expressions. [Pg.41]

In the beginning there is a general loop to decide if more lot sizing procedures should be applied to the existing quant network to meet the constraint of the minimum batch sizes of products. Then the quant network is examined, free usable stocks and free quantities of quants are made available. The material balances of any quant are calculated and decisions are taken whether quants require further explosions of their BOM. Structures for a fast cycle checking, sorting of existing quants and quant links and forecast intervals are built up. A recalculation of the due dates for all quants - also the ones of orders - can be done if specified by the user. [Pg.84]

Here = Aw (I — ty 13) (1 — ]% ) and is the free wave function of the third particle. This effective two-body force is added to the bare two-body force and recalculated at each step of the iterative procedure. [Pg.116]

Fluxes Mfc, M, K, to gas phase as well as the volumetric share of particles phase 02, are obtained evaluating corresponding fluxes from model particles and volume of model particles. The procedure of recalculating (see [6, 7]) is the following. [Pg.231]

A quantity of an appropriate sterilized placebo powder is blended with sterile excipients prior to filling (if needed) in a manner similar to the production process being simulated. The medium is passed through the run as though it were an actual product batch, and all routine procedures used in manufacture of a batch are performed. Once the medium has been processed, it is held for a period of time at least equal to that for aseptically produced materials. Any aseptic manipulations performed during and at the end of the hold period should be simulated hold times and product recalculation. [Pg.312]

All data generated in a computer system must be available, secure, and safely stored. Unauthorized people cannot have access to data files. It must be impossible to overwrite any data, but all recalculation required must generate a new data and not substitute the previous one. Safety procedures must be available. Data should be backed up periodically following specific SOPs, and backup copies must be iden-... [Pg.832]

Contrary to the usual procedure which considers only the local conformations of minimum energy, the mean-square end-to-end distance of crs-1,4-poly butadiene is recalculated taking into account the whole continuum of conformational states elastic strain on the C—C-C bond angles is also allowed, but only the values which minimize the conformational energy are retained, for every set of rotation angles. [Pg.251]

An initial guess for the pressure is assumed and the fugacity coefficient of each component in the liquid phase ( ) can be calculated. An initial guess is also assumed for the fugacity coefficient of each component in the vapour phase ( v), and consequently a first estimate of the vapour composition is evaluated. With this value of y, the fugacity coefficients in the vapour phase are recalculated using the equation of state and a second estimate for y,- is evaluated. This iterative procedure is continued until the difference between two successive values of the composition are below a predetermined error. At this point, the sum of y, is checked if the sum is different from unity a new value of the pressure is assumed for a new iteration. The iterative procedure ends when the y, differs from unity by less then a given value. [Pg.37]

We generally distinguish between two methods when the determination of the composition of the equilibrium phases is taking place. In the first method, known amounts of the pure substances are introduced into the cell, so that the overall composition of the mixture contained in the cell is known. The compositions of the co-existing equilibrium phases may be recalculated by an iterative procedure from the predetermined overall composition, and equilibrium temperature and pressure data It is necessary to know the pressure volume temperature (PVT) behaviour, for all the phases present at the experimental conditions, as a function of the composition in the form of a mathematical model (EOS) with a sufficient accuracy. This is very difficult to achieve when dealing with systems at high pressures. Here, the need arises for additional experimentally determined information. One possibility involves the determination of the bubble- or dew point, either optically or by studying the pressure volume relationships of the system. The main problem associated with this method is the preparation of the mixture of known composition in the cell. [Pg.59]

With such data, an estimate can be made of a possible evaporator configuration for a required duty, that is, the diameter, length, and number of tubes can be specified. Then heat transfer correlations can be applied for this geometry and the surface recalculated. Comparison of the estimated and calculated surfaces will establish if another geometry must be estimated and checked. This procedure is described in Example 8.12. [Pg.211]

I) are unusually large. Recalculation of the data by the new procedure gives the results tabulated in Table III. The ratios are now more of the order usually obtained for material of this sort. Also, the values for DP are shifted those for DPW are lowered to the range of the Cadoxen viscosity-DP s, while those for DPn are raised. [Pg.188]

A sequence of Newton-Raphson iterations is obtained by solving equation (4 4) redefining the zero point, p0, as the new set of parameters recalculating g and H and returning to equation (4 4). Such a procedure converges quadratically, that is, the error vector in iteration n is a quadratic function of the error vector in iteration n-1. This does not necessarily mean that the NR procedure will converge fast, or even at all. However, close to the stationary point we can expect a quadratic behaviour. We shall return later to a more precise definition of what close means in this respect. [Pg.210]


See other pages where Recalculation procedure is mentioned: [Pg.133]    [Pg.134]    [Pg.133]    [Pg.134]    [Pg.751]    [Pg.74]    [Pg.79]    [Pg.45]    [Pg.240]    [Pg.373]    [Pg.158]    [Pg.405]    [Pg.179]    [Pg.83]    [Pg.329]    [Pg.272]    [Pg.186]    [Pg.135]    [Pg.206]    [Pg.124]    [Pg.104]    [Pg.74]    [Pg.143]    [Pg.255]    [Pg.40]    [Pg.526]    [Pg.93]    [Pg.105]    [Pg.584]    [Pg.136]   
See also in sourсe #XX -- [ Pg.130 ]




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