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Variation of all parameters

Let us start from the exponential-operator description of a variation of spin-orbitals, using (8.2.18) with the infinitesimal rotation R in the form (8.2.20). For a normalized reference V) the energy after variation may be written, using (8.2.16) and expanding the exponentials. [Pg.278]

This may be written in terms of the rotation parameters using (8.2.20), which gives [Pg.278]

These commutator expressions for the derivatives are in widespread use and clearly provide a very convenient formalism, although considerable reduction is of course necessary to obtain more explicit expressions in terms of the density matrices (A, B) of the given reference function W. On making such reductions, we naturally obtain the same expressions as in Section 8.4. [Pg.279]

On turning to the variation of Cl coefficients, it is clear that the linearly independent set of CFs (assumed orthonormal) in the expansion (8.2.1) may be subjected to unitary mixing in much the same way as the basis functions. With a unitary operator Uc in CI-space we associate a matrix Uc in the usual way  [Pg.279]

The corresponding rotation (variation) of the reference state W = 4 C (C being the column of Cl coefficients C ) will be [Pg.279]


Cell separation techniques that use an inward flow component are referred to as countercurrent separation techniques. The concept of countercurrent separation is compHcated by biological variations of all parameters in equation 4. [Pg.522]

Equation (6.308) implies that the isotropic diffusive motion along the coordinate axes is independent. Here, V V/KT is the drift due to an external potential force field V, while Vcr/cr represents an internal drift caused by a concentration gradient of the traps. The term PV(e /a2) is the spurious drift term. Equation (6.308) allows spatial variations of all parameters T, V, T>. and a with inhomogeneous temperature. FromEq. (6.308), the diffusion coefficient becomes... [Pg.356]

It is possible to use the F distribution to draw boundaries for the probable variation of all parameters simultaneously for any given probability level. These boundaries will define a closed space which confines probable estimates of the model parameters. [Pg.116]

To fin d a first order saddle poiri t (i.e., a trail sition structure), a m ax-imiim must be found in on e (and on/y on e) direction and minima in all other directions, with the Hessian (the matrix of second energy derivatives with respect to the geometrical parameters) bein g varied. So, a tran sition structu re is ch aracterized by th e poin t wh ere all th e first derivatives of en ergy with respect to variation of geometrical parameters are zero (as for geometry optimization) and the second derivative matrix, the Hessian, has one and only one negative eigenvalue. [Pg.65]

For the equihbrium properties and for the kinetics under quasi-equilibrium conditions for the adsorbate, the transfer matrix technique is a convenient and accurate method to obtain not only the chemical potentials, as a function of coverage and temperature, but all other thermodynamic information, e.g., multiparticle correlators. We emphasize the economy of the computational effort required for the application of the technique. In particular, because it is based on an analytic method it does not suffer from the limitations of time and accuracy inherent in statistical methods such as Monte Carlo simulations. The task of variation of Hamiltonian parameters in the process of fitting a set of experimental data (thermodynamic and... [Pg.476]

A full set of bioreactors with pH and temperature controllers are shown in Figure 1.3. The complete set of a 25 litre fermenter with all the accessory controlling units creates a good opportunity to control suitable production of biochemical products with variation of process parameters. Pumping fresh nutrients and operating in batch, fed batch and continuous mode are easy and suitable for producing fine chemicals, amino acids, and even antibiotics. [Pg.12]

There are considerable geographic, seasonal, and short-term variations in all parameters of the Na layer, that should be taken into account by the LGS system design. The average height of the layer is at 92 km and is usually... [Pg.218]

The binary pulsar PSR1913+16. In 1974 Russell Hulse and Joseph Taylor discovered a very special pulsar PSR1916+13. A striking feature that was revealed just after its discovery was a large shift of the pulses rate with a period of a few hours. This was explained by Doppler shift, so PSR1916-H13 is in fact a binary system in which a pulsar orbits about the center of mass of the system. Thanks to the presence of this very stable local clock, Hulse and Taylor were able to obtain all the orbital parameters of this system. By studying the variations of those parameters over nearly twenty years, they... [Pg.312]

The brute force method depends on a systematic variation of all involved coefficients over a reasonable parameter space. The combination yielding the lowest goodness-of-fit measure is picked as the center for a further round with a finer raster of coefficient variation. This sequence of events is repeated until further refinement will only infinitesimally improve the goodness-of-fit measure. This approach can be very time-consuming and produce reams of paper, but if carefully implemented, the global minimum will not be missed, cf. Figures 3.4 and 4.4. [Pg.159]

Two system-dependent interpretative pictures have been proposed to rationalize this percolative behavior. One attributes percolation to the formation of a bicontinuous structure [270,271], and the other it to the formation of very large, transient aggregates of reversed micelles [249,263,272], In both cases, percolation leads to the formation of a network (static or dynamic) extending over all the system and able to enhance mass, momentum, and charge transport through the system. This network could arise from an increase in the intermicellar interactions or for topological reasons. Then all the variations of external parameters, such as temperature and micellar concentration leading to an extensive intermicellar connectivity, are expected to induce percolation [273]. [Pg.496]

In the described MC simulation, the action of several simultaneous sources of variation is considered. The explanation of the different time courses of parameter influence on volume size between sensitivity and MCCC analyses lies in the fact that classic sensitivity analysis considers variations in model output due exclusively to the variation of one parameter component at a time, all else being equal. In these conditions, the regression coefficient between model output and parameter component value, in a small interval around the considered parameter, is approximately equal to the partial derivative of the model output with respect to the parameter component. [Pg.90]

On the other hand, MCCC considers the influence of the variation of one parameter on model output in the context of simultaneous variations of all other parameters. In this situation, is smaller than 1 in absolute value and its size depends on the relative importance of the variation of model output due to the parameter of interest and the variation of model output given by the sum total of all sources (namely, the variability in all structural parameter values plus the error variance). [Pg.90]

Figure 2.12 shows the rate, the coverages, the reaction orders, and the normalized apparent activation energy, all as a function of temperature. Note the strong variations of all these parameters with temperature, in particular that of the rate, which initially increases, then maximizes and decreases again at high temperatures. This characteristic behavior is expected for all catalytic reactions, but is in practice difficult to observe with supported catalysts because diffusion phenomena come into play. [Pg.67]

The joint confidence region is the region of joint parameter uncertainty accounting for variation of all the parameters. It is defined as... [Pg.548]

These diagrams should be considered from a qualitative point of view. Furthermore, it is often not necessary to determine the trends of all the forward and reverse peaks, but only those that one judges to be the most significant. The scale of the potential scan rate in these plots is only illustrative and chosen to highlight the variations of the parameters that become evident on passing from slow to high scan rate. [Pg.93]

According to Equation 6.6, the velocity of the EOF is directly proportional to the intensity of the applied electric held. However, in practice, nonlinear dependence of the EOF on the applied electric held is obtained as a result of Joule heat production, which causes the increase of the electrolyte temperature with consequent decrease of viscosity and variation of all other temperature-dependent parameters (protonic equilibrium, ion distribution in the double layer, etc.). The EOF can also be altered during a run by variations of the protonic concentration in the anodic and cathodic electrolyte solutions as a result of electrophoresis. This effect can be minimized by using electrolyte... [Pg.160]

SEXAFS insofar has been a time-expensive probe and systematic studies with the variation of all the interface growth parameters have not been attempted. It is not merely prosaic to foresee higher availability of SR beams of higher quality in the near future, and more clever detection arrangements. SEXAFS can certainly develop quickly towards a rOle of key technique for the study of the local coordination at all growth stages and conditions of a forming solid-solid interface. [Pg.118]

In addition to these kinetic studies, there has been a considerable amount of work on the thermodynamic parameters associated with this type of reaction. Thus the interaction of [M(edta)aq] with anions of 8-hydroxyquinoline-5-sulfonic acid (oxs ), ida2- and nitrilotriace-tic acid (nta3-) was thoroughly studied for M = Y, La-Lu (except Pm) by calorimetry and pH titration,419 and AG, AH, AS and K found. Some of these values are given in Table 5. It was, however, concluded from the variation of these parameters with atomic number that all M3+ in aqueous solution have the same coordination number (nine) but that the coordination number of the [M(edta)aq] species changes between Sm3+ and Tb. ... [Pg.1088]

Alternative testing procedures have been suggested by other authors, such as the use of certain amino acids (Ooghe Kastelijn, 1985) and organic acids (Wallrauch, 1995). Flowever, because of the wide natural variation of all these components, any calculation of juice or fruit content should really be considered only as an estimate rather than an absolute value. The situation is even more complicated for a mixture of juices in a juice blend or soft drink. In this case, the parameters chosen for analysis, often potassium or phosphate, should be fairly constant between the juices within the blend, and if possible components that are characteristic of a particular juice, such as quinic acid in cranberry juice, or isocitric acid in orange, grapefruit or lemon, say, should be analysed. This type of specific marker can be used to assess the overall level of a particular juice in a blend, but not every juice has a unique marker. [Pg.273]


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Parameter variations

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