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Shape parameters

The usual experimental situation is that of a sessile drop and, as with the pendant drop, it is necessary to determine a shape parameter and some absolute length. Thus /3 may be determined by profile fitting, and Ze measured, where Ze is the distance from the plane at = 90 to the apex. If the drop rests with... [Pg.28]

The characteristic vaiue, Q, and shape parameter, [3, for the 2-parameter Weibuii distribution can be determined from the equation for the iine in the form y = A x + AO and from the equations given in Appendix X, where ... [Pg.216]

As mentioned above, the interpretation of CL cannot be unified under a simple law, and one of the fundamental difficulties involved in luminescence analysis is the lack of information on the competing nonradiative processes present in the material. In addition, the influence of defects, the surface, and various external perturbations (such as temperature, electric field, and stress) have to be taken into account in quantitative CL analysis. All these make the quantification of CL intensities difficult. Correlations between dopant concentrations and such band-shape parameters as the peak energy and the half-width of the CL emission currently are more reliable as means for the quantitative analysis of the carrier concentration. [Pg.154]

Replacing 2/8 with shape parameter c and with a specific surface, the Kozeny equation is obtained. [Pg.70]

Shape parameters control the geometric configuration of a distribution. There may be zero, one, or multiple shape parameters. [Pg.94]

The chi-square distribution gives the probability for a continuous random variable bounded on the left tail. The probability function has a shape parameter... [Pg.95]

When n < 0.7, the ln[—ln(l — a)] against In t plots show curvature and linearity is improved if the latter parameter is replaced by t. This reduces the Weibull distribution to a log-normal distribution. Since both exponential and normal distributions are special cases of the more general gamma distribution, Kolar-Anic and Veljkovic [441] compared the applicability of the Weibull and the gamma distributions. The shape parameter of the latter (e) was shown to depend exclusively on the shape parameter of the former (n). [Pg.56]

For 0.7 < n < 1, a normal distribution is obeyed indirectly, based on tl/2 via the gamma distribution with a shape parameter e =. ... [Pg.56]

Figure 1. Diagram showing the values of d orbitals in the directions of the three principal axes, as a function of the shape parameter a. Figure 1. Diagram showing the values of d orbitals in the directions of the three principal axes, as a function of the shape parameter a.
The functions I accordingly correspond to an oblate antiprism and II to a prolate antiprism. There is a simple explanation for the difference in orientation of the principal axes. The theorem that the sum of the squares of the values of the functions for a complete set (a subshell) is constant requires that the shape parameters vary in a satisfactory way with change in orientation of the principal axes. For the prolate set (II) the maximum value in the plane orthogonal to the principal axis of the function lies in the basal plane of rhe antiprism, and thus serves to increase the electron... [Pg.240]

Unfortunately the P-function proved very insensitive to shape change. Fortunately further combination of Ua-b with other universal shape parameters have proved more successful. [Pg.98]

Molecular size can be a further limiting factor in oral absorption [54]. The Lipinski Rule-of-5 proposes an upper limit of molecular weight (MW) of500 as acceptable for orally absorbed compounds [25]. High-MW compounds tend to undergo biliary excretion. Size and shape parameters are generally not measured, but rather calculated. A measured property is the so-called cross-sectional area, which is obtained from surface activity measurements [55]. [Pg.33]

Figure 31 compares the dynamic structure factors obtained from the crosslinks and the chain ends for two different Q-values. Without any analysis a strong reduction of the cross-link mobility compared to that of the chain end is obvious. A closer inspection also shows that the line-shape of both curves differs. While S(Q,t)/S(Q, 0) from the chain end decays continuously, S(Q,t) from the cross-links appears to decay faster at shorter than at longer times. This difference in line shape is quantified via the line shape parameter p. For the end-labelled chains, p is in close agreement with the p = 1/2 prediction of the... [Pg.60]

The transition from single- to many-chain behavior already becomes obvious qualitatively from a line shape analysis of the NSE spectra (see Fig. 60) [116]. For dilute solutions (c = 0.05) the line shape parameter (3 is equal to about 0.7 for all Q-values, which is characteristic of the Zimm relaxation. In contrast, in semi-dilute solutions (e.g. c = 0.18), ft-values of 0.7 are only found at larger Q-values, whereas P-values of about 1.0, as predicted for collective diffusion [see Eq. (128)] are obtained at small Q-values. A similar observation was reported by [163]. [Pg.114]

Fig. 64. Single-chain behavior in semi-dilute PDMS/d-chlorbenzene solutions. Line-shape parameter (3 as a function of Q at the concentration c = 0.18 and c = 0.45, indicating the occurance of two crossover effects, as predicted by the concept of incompletely screened hydrodynamic interactions. (----), (---) asymptotic Zimm and Rouse behavior, respectively. (Reprinted with per-... Fig. 64. Single-chain behavior in semi-dilute PDMS/d-chlorbenzene solutions. Line-shape parameter (3 as a function of Q at the concentration c = 0.18 and c = 0.45, indicating the occurance of two crossover effects, as predicted by the concept of incompletely screened hydrodynamic interactions. (----), (---) asymptotic Zimm and Rouse behavior, respectively. (Reprinted with per-...
In addition to DBT and BT, strain A11-2 could utilize methyl, dimethyl, and trimethyl DBTs as sulfur sources. The desulfurization of asymmetric alkylated DBTs was assessed to understand the sulfur specificity of this organism. It was shown to desulfurize several asymmetric alkyl DBTs up to C3-DBTs. It was shown that the rates of desulfurization depended on not only the position of alkyl substitution but also the number and length of alkyl substitution. An attempt was made to co-relate the data based on a molecular shape parameter. Selectivity of this organism was compared with R. erythropolis KA2-5-1 and, although clear differences were observed, the parameter fitting was not perfect. Two Paenibacillus strains, Paenibacillus sp. A11-1 and All-2, were patented [87] and were deposited as PERM BP-6025 and PERM BP-6026 in 1996 [122,123],... [Pg.86]

Explained variation Bonding Index Heywood shape parameter Powder bed density Particle diameter Permanent deformation pressure... [Pg.309]


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See also in sourсe #XX -- [ Pg.553 , Pg.562 , Pg.577 , Pg.584 , Pg.604 ]

See also in sourсe #XX -- [ Pg.174 ]

See also in sourсe #XX -- [ Pg.167 ]




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