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Point-successive method

With all of the point-successive methods, only one array in the computer is needed to store both o k) and 6 k+1) because the element o k) is never again needed once o k+1) is computed. This contrasts with the point-simultaneous methods, where, for each n, the elements of 6 k) must be available corresponding to the full range over which [s] m is finite. [Pg.77]

We have also learned that the point-successive methods need not demand more computer memory than point-simultaneous methods, and that the seemingly inherent asymmetry of the point-successive methods can be overcome. Furthermore, the linear methods described in this section are... [Pg.79]

There is an important disadvantage stemming from variable separation and use of the FFT, however. One is limited to the use of the point simultaneous procedure in the determination of the coefficients. That is, all of the coefficients must be computed in an iteration before they can be resubstituted back in the iterative equations. With the point successive method, the improved coefficient determined by one equation is substituted in the succeeding equation to render additional improvement. With the test data treated in this work, the point simultaneous procedure converged much more slowly than the point successive method. [Pg.327]

The existence of this situation (for nonporous solids) explains why the ratio test discussed above and exemplified by the data in Table XVII-3 works so well. Essentially, any isotherm fitting data in the multilayer region must contain a parameter that will be found to be proportional to surface area. In fact, this observation explains the success of Ae point B method (as in Fig. XVII-7) and other single-point methods, since for any P/P value in the characteristic isotherm region, the measured n is related to the surface area of the solid by a proportionality constant that is independent of the nature of the solid. [Pg.632]

The use of hops in the form of hop extract has spread rapidly the yield of the extract is better, yet insufficient. The production of a satisfactory hop extract quahty, ie, no taste difference to beer hopped by using other "natural" hop products, has appeared to be a science or art in itself Use of the right solvent and distillation is the key point, and many unsuccessful attempts have been made. The latest and most successful method, using the so-called Hquid carbon dioxide extraction, meets the high quaUty demands almost perfecdy. Preisomerization of the resins makes it uimecessary to boil them with the wort they can be added directly to the finished beer to avoid poor yield (through boiling) and the loss of resins (during fermentation). [Pg.16]

For this work, the spectrometer function s(x) was determined by the method outlined in Section II.G.3 of Chapter 2. In digitizing the data, a sample density was chosen to accommodate about 70 samples taken across the full width at half maximum of s(x). A 25-point cubic polynomial smoothing filter was used in the deconvolution procedure to control high-frequency noise. Instead of the convolution in Eq. (13), the point-successive modification described in Section III.C.2 of Chapter 3 was employed. In Eq. (24) of Chapter 3, we replaced k with the expression... [Pg.105]

III.C.3) and the use of special sampling methods to gain the rapid-convergence advantage of point-successive iteration without inducing asymmetry (Section III.C.2). [Pg.109]

If the results to this point indicated a successful method, then storage stability was evaluated. If all requirements of the protocol were met, the method was considered laboratory-validated and appropriate reports were prepared. At various stages of the protocol, we evaluated the probability of success within the budget for each method. If at any time it became apparent that the method study could not be successfully completed within budget, laboratory work was discontinued and a failure report was prepared. [Pg.5]

Differential scanning calorimetry is a technique that has recently been used for the detection of photodegradation products in solid drug substances. Even minor amounts of degradation product within a crystal lattice can provoke a significant decrease in its melting point. This method has successfully been used to monitor the photostability of nifedipine (15). [Pg.300]

There are essentially six types of procedures to solve constrained nonlinear optimization problems. The three methods considered more successful are the successive LP, the successive quadratic programming, and the generalized reduced gradient method. These methods use different strategies but the same information to move from a starting point to the optimum, the first partial derivatives of the economic model, and constraints evaluated at the current point. Successive LP is used in a number of solvers including MINOS. Successive quadratic programming is the method of... [Pg.2445]

Once the geometries of reactants and products are defined, the transition state can be located. These are points on the potential energy surface that are characterized by one, and only one, negative eigenvalue of the second derivative (Hessian) matrix. Finding such points that determine the barriers to chemical reactions remains a complicated process, but there are now several powerful techniques available. Most of the more successful methods require... [Pg.356]

Estimation of multicompartment model parameters from measured plasma samples is very similar to the procedures described previously for the two-compartment first-order absorption model. The first step is to calculate bi(C ) for each of the measured plasma sample concentrations. The values of In(C ) are then plotted versus time (t), and the points on the terminal line are identified. Linear regression analysis of the terminal line provides values for B (B = c ) and In = —m). The first residual (/ i) values are then calculated as the difference between the measured plasma concentrations and the terminal line for points not used on the terminal line. A plot of ln(i i) versus t is then employed to identify points on the next terminal line, with linear regression analysis of this line used to determine and X -. Successive method of residuals analyses are then used to calculate the remaining B and A, values, with linear regression of the n-1 residual (Rn-i) values providing the values of Bi and Aj. If a first-order absorption model is being used, then one more set of residuals (R ) are calculated, and the linear regression analysis of these residuals then provides and kg. This type of analysis is typically performed by specialized PK software when the model contains more than two compartments. [Pg.263]

This route was derived from the successful methods developed by Turner, Poliakoff and co-workers for the synthesis of similar complexes in cryogenic liquid noble gas solution [23]. Under those conditions, the low temperatures of the liquid gas solvent helped to stabilize complexes [24], such as Ni(CO)3N2, which would have been very short lived at ambient temperatures. Although this cryogenic stabilization is lost in SCF solution, the loss is compensated at least in part by the high concentration of dissolved H2 or N2, which increases the lifetime of these complexes by reducing the apparent rate of ligand dissociation. There are a number of important points which should be made about the compounds listed in the Table. [Pg.247]

A coulometric titration, like a more conventional volumetric procedure, requires some means of detecting the point of chemical equivalence. Most of the end-point detection methods applicable to volumetric analysis are equally saiisfactory here. Visual observations of color changes of indicators, as well as poicn-tionieiric, amperometric, and photometric measurements have all been used successfully. [Pg.707]


See other pages where Point-successive method is mentioned: [Pg.77]    [Pg.77]    [Pg.1221]    [Pg.29]    [Pg.233]    [Pg.420]    [Pg.23]    [Pg.95]    [Pg.322]    [Pg.66]    [Pg.286]    [Pg.76]    [Pg.145]    [Pg.316]    [Pg.59]    [Pg.419]    [Pg.286]    [Pg.30]    [Pg.52]    [Pg.204]    [Pg.451]    [Pg.1044]    [Pg.653]    [Pg.45]    [Pg.248]    [Pg.42]    [Pg.665]    [Pg.657]    [Pg.88]    [Pg.631]    [Pg.3]    [Pg.36]    [Pg.1225]    [Pg.273]    [Pg.40]    [Pg.204]   
See also in sourсe #XX -- [ Pg.76 , Pg.105 , Pg.145 , Pg.294 , Pg.327 ]




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Point method

Point-successive

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