Q-parameter

Rorabacher, D. B., Statistical Treatment for Rejection of Deviant Values Critical Values of Dixon s Q Parameter tind Related Subrange Ratios at the 95% Confidence Level, A a/. Chem. 63, 1991, 139-146. 

This case is shown schematically in Fig. 5c. In Eq. (50), qj. are generalized y-photon asymmetry parameters, defined, by analogy to the single-photon q parameter of Fano s formalism [68], in terms of the ratio of the resonance-mediated and direct transition matrix elements [31], j. is a reduced energy variable, and <7/ y, is proportional to the line strength of the spectroscopic transition. The structure predicted by Eq. (50) was observed in studies of HI and DI ionization in the vicinity of the 5<78 resonance [30, 33], In the case of a... 

QEKIRVRLSA antimicrobial peptide, 26 799-800 Qiana, 19 764 QikProp, 6 18 Qinghai Lake, 5 784 Q parameter, impeller, 16 676 QSAR analysis, 10 327t, 328-329. See also Quantitative structure—activity relationship (QSAR) studies 3D QSAR models... 

The Mathieu q parameter is given in Eq. (11.20), and the Mathieu a parameter has a value of zero in the absence of a DC potential being applied to the rods. 

Returning to the case of a single dipole, we find another parameter to be useful the fluorescence collection efficiency Q. Parameter Q is the fraction of the total energy dissipated by a fixed-power dipole that is collected by a microscope objective centered on the normal at distance r. 

Figure 9. The two largest Lyapunov exponents (a) and the bifurcation diagram (the maxima of yi) (b) versus the modulation parameter Q. Parameters are/o — 1. — y2 — 0.01 and the initial...

The rates of solvolysis of 4- and 5-substituted l-(2-thienyl)ethyl p-nitrobenzoates in 80% EtOH at 25° are correlated by a p value of —6.79,265 to be compared with —5.7 for the benzenoid reaction. Using o+ values calculated by the Dewar-Grisdale approach [Eq. (2)] incorporating q parameters derived from CNDO/2 or INDO molecular orbital procedures (which give closely similar results) gives a value of p of —7.14. For the equivalent 4-substituted l-(2-furyl)ethyl systems,266 267 however, the correlation with o is poor, p being —8.5. In this case Eq. (2) yields o+ values providing a close fit to experimental determinations with a p value that is appropriate for the benzenoid reaction. 

At first glance it seems evident that the observed spectrum of Fig. 21.11 is a sequence of Beutler-Fano interference profiles, which reverse in the Fano q parameter across the line. Although the solution may ultimately be expressed in the same mathematical form,1 a simple consideration of the excitation amplitudes... 

Fig. 22.8 The two different excitation schemes A and B used to observe the Ba 5d7d perturber as a forced autoionization resonance. Path A leads to a q parameter near zero, while B leads to a large q parameter (from ref. 21).

Here, q are the position coordinate operators of the oscillators of the bath and p are the conjugate momentum, whereas m, and m, are the corresponding reduced masses and angular frequencies. At last, the q, parameters describe the strength of the coupling between the H-bond bridge (described by the coordinate Q) and the oscillators of the bath. 

In these computations, it was assumed, following Flakus [104, 109], that there is some breaking of the IR selection rule (introduced via the q° parameter), which is increasing when the crystal order is increased, that is, when the temperature is lowered. 

The left column of Fig. 24 illustrates the role played by this possible breaking of the selection rule, via introduction of the q° parameter. 

Rorabacher, D.B., Statistical method for rejection of deviant values Critical values of Dixon s Q parameter and related subrange ratio of the 95% confidence level. Anal. Chem., 63, 139-146, 1991. 

The correlation of 31P, <5 , Ad and Q parameters versus the intermolecular P-O H-O-C and P-O- H-O-P hydrogen bond distance in the L and DL forms of O-phosphorylated amino acids has been presented (see Figure 15A). Somewhat unexpectedly, these two groups of compounds reveal opposite trends when the hydrogen-bond strength decreases the Sllr AS, and Q values increase and the d33 decreases for the L form, with a reverse scenario taking place in the case of the DL form. 

Figure 15 (A) Plots of 31P 5U, anisotropy A<5 and span Q parameter versus the intermolecular...

In some cases disks may have structures that are unstable to perturbations driven by the gravitational force that the disk exerts on itself. This is quantified by the Toomre Q parameter, given by ... 

The Xi and ]q parameters for the EE models can be optimized so that the resulting charges match gas-phase values as determined from either ab initio quantum mechanical calculations or the experimental dipole... 

This result may indicate that the ionic depolarizer reacts with two molecules (trimers) of water from the surface phase. This conclusion may not be strictly valid since the shape of the k versus mixed solvent composition dependence, calculated for the Eu(III)/Eu(II) system by means of Eq. (73), is only very slightly dependent on the b, p and q parameters. 

In some force fields, especially those using the Lennard-Jones form in eq. (2.12), tlie / Q parameter is defined as the geometrical mean of atomic radii, implicitly via the... 

The influence of Pl-S-H-C forces on P NMR shielding parameters considering thiolo sulfur was discussed earlier. Analysis of the data proved that the influence of this type of interaction on P NMR shielding is much smaller compared to the analogous thiono S -CH4 contacts. It was concluded that the most sensitive parameter, which characterizes the C-H-S weak contacts, is span Q parameter defined as 033-011. 

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