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Statistic operator

The quintessential statistical operation in analytical chemistry consists in estimating, from a calibration curve, the concentration of an analyte in an unknown sample. If the regression parameters a and b, and the unknown s analytical response y are known, the most likely concentration is given by Eq. (2.19), y being the average of all repeat determinations on the unknown. [Pg.108]

If the dependence of nA and nB on q is taken into account in the calculation of the statistical operators for heavy particles, we obtain the improved Condon approximation (ICA) which differs from Eq. (17) only by the change of p and p°f to p, and pf, respectively. In the classical limit for p, and p/ the expression for the transition probability takes the form... [Pg.112]

There are two (count them two) more very critical developments that come from this partitioning of sums of squares. First, the correlation coefficient is not just an arbitrarily chosen computation (or even concept), but as we have seen bears a close and fundamental relationship to the whole ANOVA concept, which is itself a very fundamental statistical operation that data is subject to. As we have seen here, all these quantities - standard deviation, correlation coefficient, and the whole process of decomposing a set of data into its component parts - are very closely related to each other, because they all represent various outcomes obtained from the fundamental process of partitioning the sums of squares. [Pg.479]

Here pq is the diagonal matrix element of the equilibrium statistical operator of... [Pg.88]

For example, in the early school years we learn a package of arithmetic in which the numbers have well-known operations. In college, we may learn another package that talks about statistical operators. The package does not define any new types. We are still talking about the numbers we have always known it s just that we now have new information about the same types. [Pg.321]

In an extended version of the hopping concept, positional ( off-diagonal ) disorder in addition to energetic ( diagonal ) disorder has been introduced [54,63]. The simplest ansatz was to incorporate this by allowing the electronic overlap parameter 2ya to vary statistically. Operationally, one splits this parameter into two site contributions, each taken from a Gaussian probability density, and defines a positional disorder parameter I, in addition to the energetic disorder parameter cr. [Pg.19]

The previous discussion of standard deviation and related statistical analysis placed emphasis on estimating the reliability or precision of experimentally observed values. However, standard deviation does not give specific information about how close an experimental mean is to the true mean. Statistical analysis may be used to estimate, within a given probability, a range within which the true value might fall. The range or confidence interval is defined by the experimental mean and the standard deviation. This simple statistical operation provides the means to determine quantitatively how close the experimentally determined mean is to the true mean. Confidence limits (Lj and L2) are created for the sample mean as shown in Equations 1.6 and 1.7. [Pg.30]

We quote some central formulas valid for an exact quantum description of EET and related optical spectra. The formulas will serve as reference relations to change to a mixed quantum classical description. To present the full quantum formulas we need the so-called site representation of the overall statistical operator ... [Pg.47]

The vibrational equilibrium statistical operators Rm and the time evolution operators Um(t) are defined by the Hamiltonians Hm = Vo + Tm- -Umeg (with the PES given in Eq. (11)). [Pg.48]

Here, Ro denotes the respective statistical operator for the nuclear coordinate equilibrium motion in the electronic ground state of the CC. The dn are scalar... [Pg.48]

Since the photon version of the reservoir correlation functions Cuv includes the photon statistical operator which is defined by the projector on the photon vacuum the correlation functions simply read... [Pg.52]

It describes single chromophore excited state decay where the statistical operator Rme defines intra chromophore vibrational equilibrium in the excited electronic state. The whole mefl has to be taken at time argument t — t and, then, to be multiplied to A (f,f k) in Eq. (68). [Pg.67]

We have so far limited ourselves to a classical description, the natural requirement for which is the condition /, /" —> oo. In order that the description is valid for any angular momentum value, it is necessary to employ the quantum mechanical approach. We presume that the reader is acquainted with the density matrix (or the statistic operator) introduced into quantum mechanics for finding the mean values of the observables averaged over the particle ensemble. Under the conditions and symmetry of excitation considered here one must simply pass from the prob-... [Pg.57]

When the product of monomer relative reactivity ratios is approximately one r x r2 = 1), the last inserted monomeric unit in the chain does not influence the next monomer incorporation and Bernoullian statistics govern the formation of a random copolymer. When this product tends to zero (r xr2 = 0), there is some influence from the last inserted monomeric unit (when first-order Markovian statistics operate), or from the penultimate inserted monomeric units (when second-order Markovian statistics operate), and an alternating copolymer formation is favoured in this case. Finally, when the product of the reactivity ratios is greater than one (r x r2 > 1), there is a tendency for the comonomers to form long segments and block copolymer formation predominates (or even homopolymer formation can take place) [448],... [Pg.180]

In linear response theory the optical activity is obtained from the part of the generalized susceptibility involving the temporal correlations of the electric and magnetic polarization fields46,47. For a system such as a normal fluid, described by a statistical operator that is invariant under space and time translations, the appropriate retarded Green function is,... [Pg.16]

This component carries out the mathematical and statistical operations which enable comparisons with the calibrated standards and determination of the analyte concentration. [Pg.665]

Although the subject is much too large to treat in depth in a single chapter, it is hoped that a brief discussion of the more important statistical operations will encourage the reader to seek more detailed information. [Pg.531]

A sterility test attempts to infer the state (sterile or non-sterile) of a batch from the results of an examination of part of a batch, and is thus a statistical operation. Suppose that p represents the proportion of infected containers in a batch and q the proportion of non-infected containers. Then, p + q=lor q=l-p. [Pg.373]

Let us calculate the proton current density of I due to hopping (at room temperature). On calculating I, we apply the method based on the usage of the statistical operator, proposed earlier by Hattori [173] for another type of systems. Setting J(R, ) kBT where kBT 300 K, with accuracy to terms of order J2(Rm) we have for the current density... [Pg.405]


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