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Spectrum point

After the data are acquired, transient signals taken at individual wavelengths can be analyzed for kinetic information or an entire time-resolved spectrum can be synthesized. This is achieved by instructing the computer to assemble a point-by-point spectrum, corresponding to a particular delay time after the photolysis pulse. The spectrum is constructed out of points that are 4 cm-1 apart and is similar to a spectrum produced by a normal IR spectrometer but with 30 nsecond time resolution ... [Pg.294]

One can describe the state of affairs without reference to the fourth dimension as follows. In the case of the point spectrum the geometry of Riemann (constant positive curvature) reigns in momentum space, while in the case of the continuous spectrum the geometry of Lobatschewski (constant negative curvature) applies. [Pg.292]

The geometrical meaning of the Schrodinger equation (9.1) is not as concrete in the case of the continuous spectrum as it is in the case of the point spectrum. Therefore, in applications it is better to derive formulas first for the point spectrum and only at the end allow the principal quantum number n to take pure imaginary values. This procedure allows one to see that the ( , a) s are analytic functions of n and a that, for pure imaginary values of n and a, differ from the corresponding functions of the continuous spectrum... [Pg.292]

For the case of a point spectrum, oPr the spectral function,p, is a constant function of E, with discrete steps dco,t at each point eigenvalue Ek. For the continuous spectrum, aAC, one obtains... [Pg.94]

In general, relation (21) is false one only has exp(tresidual spectrum, but it is false for the continuous spectrum there exist abstract operators A with empty spectrum, but such that the continuous spectrum of S t) is the circle of radius exp(Trt) thus the solutions of equation (20) grow exponentially in time. [Pg.215]

Energy analysis of the photoelectrons is carried out by a spectrometer of which there are two types cylindrical and spherical sector. In both cases, they are in the form of a capacitor that focuses electrons with the same selected energy level to a detection point, spectrum acquisition is carried out sequentially by scanning the selected energy. [Pg.102]

The fact that K is time independent opens the possibility to work with eigenfunction expansions. We consider the case in which K has pure point spectrum, i.e. no continuum. This is always the case for /V-level models with periodic time dependent fields. Further remarks on other cases are given in Appendix A. [Pg.153]

Figure 3 presents the reconstructed mass spectrum of the first discriminant function which separated the river and marine stations in the DiD2-map of Figure 1. The positive D-function describes the covariant mass peaks with higher intensities with respect to the zero point spectrum. All sample spectra with such characteristics will have positive score values. This spectrum is a representation of the characteristics of riverine material. The negative D-function spectrum in Figure 3 is indicative of the marine characteristics. The D spectrum shows a number of mass peaks indicative for carbohydrates, lignin and proteinaceous material (12). The mass peak m/z=86 and 100 are uncommon and a special characteristic of these fluvial samples. It can be speculated to be the molecular ion of (alkyl)thiadiazole (a metal binding pollutant), however a cyclic ketone, short chain alcohol or unsaturated acid are also possibilities. These mass peaks were chosen for further study because of their rare occurrence and their high discriminating power in the factor-discriminant analysis. Figure 3 presents the reconstructed mass spectrum of the first discriminant function which separated the river and marine stations in the DiD2-map of Figure 1. The positive D-function describes the covariant mass peaks with higher intensities with respect to the zero point spectrum. All sample spectra with such characteristics will have positive score values. This spectrum is a representation of the characteristics of riverine material. The negative D-function spectrum in Figure 3 is indicative of the marine characteristics. The D spectrum shows a number of mass peaks indicative for carbohydrates, lignin and proteinaceous material (12). The mass peak m/z=86 and 100 are uncommon and a special characteristic of these fluvial samples. It can be speculated to be the molecular ion of (alkyl)thiadiazole (a metal binding pollutant), however a cyclic ketone, short chain alcohol or unsaturated acid are also possibilities. These mass peaks were chosen for further study because of their rare occurrence and their high discriminating power in the factor-discriminant analysis.
Figure 2. Zero point spectrum of the pyrolysis mass spectral data file of the sample sites shown in the discriminant function score map in Figure 1. Figure 2. Zero point spectrum of the pyrolysis mass spectral data file of the sample sites shown in the discriminant function score map in Figure 1.
Figure 14. The region of OD stretching fundamental in the spectrum of HDO in Nafion 125 (sodium form, 95% H, 5% D). The top spectrum was obtained by the sandwiched film technique, the others by the vapor equilibrium technique. The point-by-point spectrum was recorded with 3-min time lapses between points to minimize... Figure 14. The region of OD stretching fundamental in the spectrum of HDO in Nafion 125 (sodium form, 95% H, 5% D). The top spectrum was obtained by the sandwiched film technique, the others by the vapor equilibrium technique. The point-by-point spectrum was recorded with 3-min time lapses between points to minimize...
Mixing In addition to ergodicity, A = 0 is the only member of the point spectrum. [Pg.370]

Fig. 3.3-2 A simulated 1000-point spectrum with five well-separated Lorentzian peaks of various widths, without (a) and with (b) Gaussian noise, and the noisy spectrum after filtering with a 25-point smoothingpolynomial of (c) first-order, (d) third-order, and (e) fifth-order respectively. Parameters used for the simulated spectrum ax = 0.001, b4 = 300, c, = 1, 2 = 0.003, b2 = 600, c2 = 1, a3 = 0.01, b3 = 750, c3=l,a4 = 0.03, b4 = 850, c4 = 1,<% = 0.1, b5 = 925, c5= 1, na = 0.1. Curve (f) shows the fit of the same noisy data set (b) after using Barak s adaptive-degree polynomial filter for a 25-point moving polynomial of order between 0 and 10. Fig. 3.3-2 A simulated 1000-point spectrum with five well-separated Lorentzian peaks of various widths, without (a) and with (b) Gaussian noise, and the noisy spectrum after filtering with a 25-point smoothingpolynomial of (c) first-order, (d) third-order, and (e) fifth-order respectively. Parameters used for the simulated spectrum ax = 0.001, b4 = 300, c, = 1, 2 = 0.003, b2 = 600, c2 = 1, a3 = 0.01, b3 = 750, c3=l,a4 = 0.03, b4 = 850, c4 = 1,<% = 0.1, b5 = 925, c5= 1, na = 0.1. Curve (f) shows the fit of the same noisy data set (b) after using Barak s adaptive-degree polynomial filter for a 25-point moving polynomial of order between 0 and 10.
Pulse delay Acquisition time Spectral width Data points/spectrum Free Induction Decays (FID s) accumulated ... [Pg.247]

The unbounded domain causes difficulties, on the one hand, via continuous spectrum which may - and does - interfere with the pure point spectrum required for our bifurcation analysis. The unbounded domain is necessary, on the other hand, to correctly incorporate the Euclidean symmetry of the problem under translations and rotations. In section 3.2 below we will specifically address competing and coexisting pinning and drifting phenomena. Such phenomena are predicted for the light-sensitive BZ system, when full Euclidean symmetry is broken towards a mere translational lattice symmetry, by choosing a spatially periodic lighting. [Pg.72]

Prom [72] we recall the existence of a center manifold Ai associated to a rigidly rotating reference spiral, alias a relative eqnilibrium SE 2)u see also (3.1)-(3.7) above. In fact, the center manifold M. accounts for all solutions which remain in a neighborhood of the relative equilibrium SE 2)ut, for all positive and negative times. In particular, all bifurcations due to point spectrum on the imaginary axis of the linearization L from... [Pg.82]

The asymptotic N -> oo) behavior of the swelhng factor is determined by the fixed-point spectrum of the effective coupling function, defined as the roots g K) of the nonlinear equation... [Pg.309]

Fig. 8. Various types of junction points arranged in the order of decreasing cohesive energy (junction point spectrum). Fig. 8. Various types of junction points arranged in the order of decreasing cohesive energy (junction point spectrum).
Some changes to which the gel is subjected, owing to varying reactions or conditions like swelling, contraction, temperature change and so on, may be expressed in terms of a shift of its junction point spectrum. [Pg.498]

This implies that a narrow junction point spectrum is required Gels in which the spectrum is broad, (ranging from lower to higher energies of cohesion) will be devoid of thixotropy. [Pg.510]

In odier words, we may say that the junction point spectrum of the gel (cf. p. 497) is chaiiged in the corresponding sense. The idea suggested by Hofmeister, the... [Pg.566]


See other pages where Spectrum point is mentioned: [Pg.529]    [Pg.297]    [Pg.296]    [Pg.150]    [Pg.287]    [Pg.292]    [Pg.458]    [Pg.44]    [Pg.87]    [Pg.6385]    [Pg.182]    [Pg.462]    [Pg.81]    [Pg.388]    [Pg.236]    [Pg.337]    [Pg.6384]    [Pg.6385]    [Pg.4]    [Pg.288]    [Pg.82]    [Pg.497]    [Pg.499]    [Pg.502]    [Pg.503]    [Pg.503]    [Pg.505]    [Pg.511]    [Pg.547]    [Pg.572]    [Pg.572]   
See also in sourсe #XX -- [ Pg.145 ]




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