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Matrix intensities

Fitting the data to this simple phenomenological model affords a substantial dimensionality reduction while preserving most of the original fidelity. Each data matrix (intensity vs. frequency and time) is reduced to two vectors, namely temperature and area versus time. A representative example of the temperature and area curves are presented in Fig 5. The standard error in the area was about ten times greater than temperature, and is periodically displayed in Fig 5. Initial temperatures were 1700-2000 K and often followed an exponential decay with rates between 0.91-1.24 s Examining Fig 2, we note that errors in the residuals due to temporal aliasing contribute less than 0.5% since the interferometer scanned at least 16 times faster than the temperature decay rate. [Pg.283]

The matrix-isolated spectra of HNCO, DNCO, HNCS, and DNCS in the far-i.r. (10—50 cm ) and of the CNO anion in the i.r. (550— 5000 cm ) have been recorded. The acid molecules were isolated in both argon and nitrogen matrices at 13 K although no absorptions attributable to the guest molecules were observed in the nitrogen matrix, intense bands were recorded in the argon matrix. These bands are best explained by rotation of the molecule about an axis close to the axis of least inertia. Isotopically enriched cyanate anions have been prepared by direct oxidation reactions and introduced into KCl and KBr single crystals to a maximum concentration of ca. 5 wt. The i.r. spectra of the resultant cyanate ion isotopic species show that these ions are dissolved in the form of a solid solution. [Pg.287]

The line of insignificant intensity with g = 2,003, close to the g-factor-free electron 20,023, has been carried to unpaired electrons atoms of carbon of a polyacethylene matrix. Intensity of electrons signals for atoms molybdenum essentially above, than for electrons of carbon atoms of a matrix. It is possible to conclude signal strength, that the basic contribution to paramagnetic properties of a composite bring unpaired electrons of atoms of molybdenum. [Pg.91]

Figure 7.9 Superimposed spectra during the depth scan of an ARA membrane (A) and (A ) intensity of the nitrate band in the nitric acid solution and within the membrane respectively, (B) nitrate absence in the hydrochloric solution, (C) water intensity, (D-F) membrane matrix intensities. Figure 7.9 Superimposed spectra during the depth scan of an ARA membrane (A) and (A ) intensity of the nitrate band in the nitric acid solution and within the membrane respectively, (B) nitrate absence in the hydrochloric solution, (C) water intensity, (D-F) membrane matrix intensities.
The Co-Occurrence Matrix is a function of two variables i and j, the intensities of two pixels, each in E it takes its elements in N (set of natural integers). [Pg.232]

The parameters of this matrix are the image / and the vector d written by [dx, dy] in cartesian coordinates or [ r, 0] in polar coordinates. The number of co-occurrence on the image / of pairs of pixels separated by vector d. The latter pairs have i and j intensities respectively, i.e. [Pg.232]

For an operation of seginentation, the vector d will have to be calculated that matrix allows to separate the noise of defects. We search transitions of frontiers, there is all couples (i, j) of pixels such that i is an intensity linked to the noise and j an intensity linked to the defect. [Pg.233]

The vanishing of the YM field intensity tensor can be shown to follow from the gauge transformation properties of the potential and the field. It is well known (e.g., Section II in [67]) that under a unitary transfoiination described by the matrix... [Pg.150]

The intensities are plotted vs. v, the final vibrational quantum number of the transition. The CSP results (which for this property are almost identical with CI-CSP) are compared with experimental results for h in a low-temperature Ar matrix. The agreement is excellent. Also shown is the comparison with gas-phase, isolated I. The solvent effect on the Raman intensities is clearly very large and qualitative. These show that CSP calculations for short timescales can be extremely useful, although for later times the method breaks down, and CTCSP should be used. [Pg.374]

Here, Ri f and Rf i are the rates (per moleeule) of transitions for the i ==> f and f ==> i transitions respeetively. As noted above, these rates are proportional to the intensity of the light souree (i.e., the photon intensity) at the resonant frequeney and to the square of a matrix element eonneeting the respeetive states. This matrix element square is oti fp in the former ease and otf ip in the latter. Beeause the perturbation operator whose matrix elements are ai f and af i is Hermitian (this is true through all orders of perturbation theory and for all terms in the long-wavelength expansion), these two quantities are eomplex eonjugates of one another, and, henee ai fp = af ip, from whieh it follows that Ri f = Rf i. This means that the state-to-state absorption and stimulated emission rate eoeffieients (i.e., the rate per moleeule undergoing the transition) are identieal. This result is referred to as the prineiple of microscopic reversibility. [Pg.389]

Clearly, Bi f embodies the final-level degeneraey faetor gf, the perturbation matrix elements, and the 2n faetor in the earlier expression for Ri f. The spontaneous rate of transition from the exeited to the lower level is found to be independent of photon intensity, beeause it deals with a proeess that does not require eollision with a photon to oeeur, and is usually denoted Ai f. The rate of photon-stimulated upward transitions from state f to state i (gi Rf i = gi Ri f in the present ease) is also proportional to g(cOf,i), so it is written by eonvention as ... [Pg.391]

Molecular point-group symmetry can often be used to determine whether a particular transition s dipole matrix element will vanish and, as a result, the electronic transition will be "forbidden" and thus predicted to have zero intensity. If the direct product of the symmetries of the initial and final electronic states /ei and /ef do not match the symmetry of the electric dipole operator (which has the symmetry of its x, y, and z components these symmetries can be read off the right most column of the character tables given in Appendix E), the matrix element will vanish. [Pg.410]

Standardizing the Method Equations 10.32 and 10.33 show that the intensity of fluorescent or phosphorescent emission is proportional to the concentration of the photoluminescent species, provided that the absorbance of radiation from the excitation source (A = ebC) is less than approximately 0.01. Quantitative methods are usually standardized using a set of external standards. Calibration curves are linear over as much as four to six orders of magnitude for fluorescence and two to four orders of magnitude for phosphorescence. Calibration curves become nonlinear for high concentrations of the photoluminescent species at which the intensity of emission is given by equation 10.31. Nonlinearity also may be observed at low concentrations due to the presence of fluorescent or phosphorescent contaminants. As discussed earlier, the quantum efficiency for emission is sensitive to temperature and sample matrix, both of which must be controlled if external standards are to be used. In addition, emission intensity depends on the molar absorptivity of the photoluminescent species, which is sensitive to the sample matrix. [Pg.431]

Sensitivity Sensitivity in flame atomic emission is strongly influenced by the temperature of the excitation source and the composition of the sample matrix. Normally, sensitivity is optimized by aspirating a standard solution and adjusting the flame s composition and the height from which emission is monitored until the emission intensity is maximized. Chemical interferences, when present, decrease the sensitivity of the analysis. With plasma emission, sensitivity is less influenced by the sample matrix. In some cases, for example, a plasma calibration curve prepared using standards in a matrix of distilled water can be used for samples with more complex matrices. [Pg.440]

Ema data can be quantitated to provide elemental concentrations, but several corrections are necessary to account for matrix effects adequately. One weU-known method for matrix correction is the 2af method (7,31). This approach is based on calculated corrections for major matrix-dependent effects which alter the intensity of x-rays observed at a particular energy after being emitted from the corresponding atoms. The 2af method corrects for differences between elements in electron stopping power and backscattering (the correction), self-absorption of x-rays by the matrix (the a correction), and the excitation of x-rays from one element by x-rays emitted from a different element, or in other words, secondary fluorescence (the f correction). [Pg.285]

Other wet high intensity units provide configurations that have rotating matrixes similar to wet dmm units having cooled electro cods. StiU others fad. into the category of filters using cryogenicady cooled cods and stationary matrixes (Eig. 10). [Pg.426]

Fig. 10. Wet high, intensity magnetic separator using cryogenically cooled coils and a stationary matrix where A is the feed control for top-fed or retention time control for underfed operation and B is the feed control for underfed or retention time control for top-fed operation. Fig. 10. Wet high, intensity magnetic separator using cryogenically cooled coils and a stationary matrix where A is the feed control for top-fed or retention time control for underfed operation and B is the feed control for underfed or retention time control for top-fed operation.

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See also in sourсe #XX -- [ Pg.337 , Pg.343 , Pg.351 , Pg.352 ]




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