Stationary excitation

The stationary excitation spectrum of the predissociated C state of Na is presented in the insert of Fig. 21. It shows a pronounced vibrational... 

By analyzing the spectra of the low-temperature recombination luminescence of GaP crystals under conditions of stationary excitation, Tomas et al. [63] have determined the distances of electron tunneling. The spectra of this luminescence at 1.6 K consist of a large number of intensive narrow lines. The appearance of these lines is due to the fact that the energy of the quantum hv emitted as a result of electron tunneling between the charged donor and the acceptor depends on the distance, R, between the reagents... 

The exponential dependence of the efficiency of fluorescence quenching on the distance between a donor and an acceptor may be explained by the tunneling mechanism of electron transfer from a singlet-excited molecule of the donor to the acceptor. Indeed, in case of stationary excitation of donor particles, the value of J is determined by the stationary concentration n of the excited donor particles J = An where A is a constant. The value of n is, in its turn, inversely proportional to the rate constant, k, of deactivation of excited particles nft = nJexcexciting light, quantum yield of excited molecules, and n is the concentration of non-excited donor molecules. Thus, J = AnJexc4>lk. Hence, one can easily obtain... 

IET serves as a theoretical basis not only for fluorescence and photochemistry but also for photoconductivity and for electrochemiluminescence initiated by charge injection from electrodes. These and other related phenomena are considered. The kinetics of luminescence induced by pulse and stationary excitation is elucidated as well as the light intensity dependence of the fluorescence and photocurrent. The variety and complexity of applications proves that IET is a universal key for multichannel reactions in solutions, most of which are inaccessible to conventional (Markovian) chemical kinetics. 

The general depiction of a one-color, three-photon ionization contains four experimental outcomes. These occur when the energy of the multiple of excitation photons (a) does not match a stationary excited state of the system or (b) matches some stationary resonance RS state of the system or when the ion is produced (c) in an excited, ion state (/ ), or (d) in excited, continuum states which, thereafter, ionize (i.e. ATI). The kinetic energy of the ejected electron in (b) is KE = 3hv - /. In cases (c) and (d), electrons of energy KE2 = 3hv -I and KE3 = 4hv - /, respectively, are observed (Figure 4). 

On the other hand, the depolarized low-frequency light scattering (LS) measurement under stationary excitation in a right-angled configuration, offers the information on the fluctuation in the frequency domain. The frequency spectrum obtained by this measurement can be represented as ... 

The depolarized low-frequency LS measurement is performed under stationary excitation by means of a double monochromator for a wide frequency range and a Sandercock-type tandem Fabry-Perot interferometer for a high-resolution study. The same samples as above are measured using 1 cm glass cell. The LS is measured under a depolarized condition in a right-angled configuration. 

The result of our analysis for stationary excitation showed the negative amplitude of the decay correlation function inherent to a system which can only be in one state either the ground or the excited state. In contrast to excited... 

Instead of measuring the lifetime of a single molecule with pulsed excitation the time dependent intensity of a single molecule under stationary excitation can be measured. Fig. 4.8 shows the first fluctuation of the single DNA molecule. As evident from Fig. 4.8 the data are almost identical to a patch clamp signal from the experiments of Neher and Sackmann showing single ion channels and the fluctuation of the ion current. 

Fig. 8.5. Principle of the modulated excitation approach in a LSCM. In an LSCM, variation of scanning speed/pixel dwell time is from the sample point of view equivalent to varying the duration of the excitation pulse of a stationary excitation field...

Several calculations have been reported for the AGP-based polarization propagator applied to atoms and small molecular systems. When the Eq. (5.67) is satisfied, individual stationary excited states can be obtained as excitations from the AGP reference state. Thus, starting from an energy optimized AGP, the vertical excitation (and de-excitation energies, when the AGP is not the ground state) determines potential energy surfaces and wavefunctions for other states. B. Weiner and Y. Ohrn calculate the ground state of the LiH... 

The absolute degree of interpolymer association cannot be, however, estimated from the value of Fg/Fm. As the extensive studies on solvent effects on exciplex lifetime and emission efficiency indicate (16), the exciplex emission intensity under the stationary excitation condition decreases with increasing the solvent polarity because of decreases in both the exciplex lifetime and the emission probability. 

Case 3. The quenching is dynamic, that is the fluorophore reacts with the quencher within the lifetime of the excited state both quencher and fluorophore are completely solubilized. The total intensity of the fluorescence at stationary excitation as well as at pulse excitation is the result of the simultaneous emission by fluorophore molecules from the micelles, containing 0,1,2,... etc. molecules of quencher. One can consider the fluorophore molecules located in micelles with equal number of quencher molecules to be an ensemble and the total emission as a sum of the emission of all ensembles. The... 

The stipulation leading to equation (11) is fairly valid for high speed compound helicopters (y 1.6) since the spatial separation r is dominated by V(t2 - tj). Further, the excitation, though nonstationary, can be treated as a stationary excitation modulated by a delay filteri2.i3. 

Shinozuka M, Sato Y (1967) Simulation of nonstationary random process. J Eng Mech ASCE 93 11-40 Solomos GP, Spanos PD (1984) Oscillator response to non-stationary excitation. Am Soc Mech Eng Appl Mech Div AMD 65 159-170 Spanos PD (1983) ARMA algtmthms for ocean wave modeling. Trans ASME J Energy Resour Technol 105 300-309 Spanos PD (1986) Filter approach to wave kinematics approximations. Appl Ocean Res 8 2-7 Spanos PD, Miller SM (1994) Flilbert transform generalization of a classical random vibration integral. J Appl Mech 61 575-581... 

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