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Variance, external

With the addition of increasing amounts of electrolyte this variance decreases and an approximate linear relationship between internal and external pH exists in a 1 Af electrolyte solution. The cell-0 concentration is dependent on the internal pH, and the rate of reaction of a fiber-reactive dye is a function of cell-0 (6,16). Thus the higher the concentration of cell-0 the more rapid the reaction and the greater the number of potential dye fixation sites. [Pg.355]

Another situation is found for the Na+ ions. When the membrane is permeable to these ions, even if only to a minor extent, they will be driven from the external to the internal solution, not only by diffusion but when the membrane potential is negative, also under the effect of the potential gradient. In the end, the unidirectional flux of these ions should lead to a concentration inside that is substantially higher than that outside. The theoretical value calculated from Eq. (5.15) for the membrane potential of the Na ions is -1-66 mV. Therefore, permeabihty for Na ions should lead to a less negative value of the membrane potential, and this in turn should lead to a larger flux of potassium ions out of the cytoplasm and to a lower concentration difference of these ions. All these conclusions are at variance with experience. [Pg.578]

Because of these complications, regardless of the very high within-run precision attainable via TIMS or ICP-MS, the true precision of the runs (as opposed to the internal or within run precision provided by the TIMS or ICP-MS operating software) can only be reliably established by replicate analyses of natural samples. One useful approach is to establish the external variance of a measurement technique by subtracting the internal variance from the total (= run-to-run) variance from replicate analyses, e.g.. [Pg.632]

Adaptive self-control of the energy contribution in the oscillating process, exhibited in the sustaining of a value for the system s oscillation amplitude and frequency which is stable over significant variance of the amplitude of external influence, the quality factor of the oscillator (the load) and other external variables. [Pg.118]

The protons Ha and Hb are totally in different chemical environments. There is a significant difference in their chemical shifts because of the variance in the resonance positions of their nuclei. Thus, Ha experiences a total magnetic field comprising of external field (Ho) and local field due to Hb as shown in Figure 23.3. [Pg.345]

The catalytic isomerization of 1-methylnaphthalene and all lation of 2-methylnaphtha-lene with methanol were studied at ambient pressure in a flow-type fixed bed reactor. Acid zeolites with a Spaciousness Index between ca. 2 and 16 were found to be excellent isomerization catalysts which completely suppress the undesired disproportionation into nwhthalene and dimethylnaphthalenes due to transition state shape selectivity. Examples are HZSM-12, H-EU-1 and H-Beta. Optimum catalysts for the shape selective methylation of 2-methylnaphthalene are HZSM-5 and HZSM-li. All experimental finding concerning this reaction can be readily accounted for by conventional product shape selectivity combined with coke selectivation, so there is no need for invoking shape selectivity effects at the external surface or "nest effects", at variance with recent pubhcations from other groups. [Pg.291]

The GED approach is a general procedure based on the exact solutions to the n-electron system. Only one Hamiltonian is required at variance with the infinite Hamiltonian approach (defined on the parametric -space) characteristic of the BO scheme. All the base functions are expanded from a unique origin of the I-frame. The characteristics of the n-electrons diabatic base functions are independent from the positions taken by the sources of the external potential. [Pg.192]

Next, we define a parallel set of NPD function in continuous flow recirculating systems. We restrict our discussion to steady flow systems. Here, as in the case of RTD, we distinguish between external and internal NPD functions. We define fk and 4 as the fraction of exiting volumetric flow rate and the fraction of material volume, respectively, that have experienced exactly k passages in the specified region of the system. The respective cumulative distribution functions, and /, the means of the distributions, the variances, and the moments of distributions, parallel the definitions given for the batch system. [Pg.376]

The same modeling scheme has been employed by Toropov et al. [72], who once again used the DCW descriptor. But, in this case, the descriptor denoted the variance in a set of 26 organic solvents coded with the SMILES notation. The model was externally validated, which confirmed its predictivity. The values of... [Pg.211]

Personal experience has shown that PLS often provides lower RMSEC values than PCR. The improvement in calibration performance must also manifest itself in predictions for independent samples. Therefore, a thorough evaluation of PCR versus PLS in any calibration application must involve using a large external validation data set with a comparison of RMSEPpcr and RMSEPpls in conjunction with respective regression vector norms or other variance expressions. [Pg.150]

Equation 5.29 shows that the variance of the response curve is separable into contributions from the axial dispersion, and from the external and internal mass transfer. Measurements at different velocities lead to an estimate of all transport coefficients. [Pg.90]

The random process input variables represent those variables that influence the process evolution, but they can hardly be influenced by any external action. Frequently, the random input variables are associated with deterministic input variables when the latter are considered to be in fact normal randomly distributed variables with mean Xj, j = 1, N ( mean expresses the deterministic behaviour of variable Xj) and variance j = 1, N. So the probability distribution function of the Xj variable can be expressed by the following equation ... [Pg.2]


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See also in sourсe #XX -- [ Pg.107 ]




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