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Decay enhancement

Most models for SEF focus on the plasmonics, and treat the molecule as a classical dipole. While the plasmonics models increasingly give more realistic results for the plasmon observed in the system, the treatment of the molecule, and thus the molecule-metal system, is not always as well developed. In their 2005 paper, Johansson, Xu, and Kail [44] present a unified model of enhanced Raman scattering and enhanced fluorescence within the context of quantum optics. This model is easily modified to include the field enhancement (M) and decay enhancement (Md), which may be calculated through plasmonics methodology. [Pg.75]

DNA, RNA and nucleotides have a profound effect on the formation and decay of free radical of AA and formation of AA - MM complex (Chlnoy et al., 1974) (ref. Chapter 1). Addition of DNA and RNA to AA In the presence of 2 2 resulted in the enhanced formation of the free radical of AA and Its earlier and faster decay. Enhancement in the signal height varied with the concentration of the nucleic acid and so did the rate of decay. During the reaction of AA with DNA or RNA in the presence of 2 2 observed that... [Pg.310]

The simplest model of time-dependent behavior of a neutron population in a reactor consists of the point kinetics differential equations, where the space-dependence of neutrons is disregarded. The safety of reactors is greatly enhanced inherently by the existence of delayed neutrons, which come from radioactive decay rather than fission. The differential equations for the neutron population, n, and delayed neutron emitters, are... [Pg.211]

Figure 5 shows the enhanced concentration of oppositely charged ions near the charged surface, and the depleted concentration of similarly charged ions near the charged surface due to electrostatic attractions and repulsions. Both factors reduce the effective potential, /, as the distance from the surface, X, increases. The distance at which / drops to 1/ (37%) of its value at the Stem plane is called the counterion atmosphere decay distance,... [Pg.545]

Enhanced Reaction Kinetics. For reactions involving tritium, the reaction rates are frequendy larger than expected because of the ionising effects of the tritium P-decay. For example, the uncataly2ed reaction 2T2+O2 — 2X20 can be observed under conditions (25°C) for which the analogous reaction of H2 or D2 would be too slow for detection (30). [Pg.14]

The triplet-state energy level of oxytetracycline, the excitation maximum (412 nm), lifetimes of Eu-OxTc (58 p.s) and Eu-OxTc-Cit (158 p.s), were determined. A 25-fold luminescence enhancement at 615 nm occurs upon addition of citrate within a short 5-min incubation time at neutral pH. It s accompanied by a threefold increase of the luminescence decay time. The optimal conditions for determination of OxTc are equal concentrations of Eu(III) and citrate (C = T lO mol-E ), pH 7.2. Eor determination of citrate, the optimal conditions concentrations of Eu(HI) and OxTc are 1 0,5 (Cg = MO Huol-E-i, = 5-10-HuohE-i) at pH 7.2. [Pg.391]

Introduction of the surface-nucleation mechanism in numerical computation of elastic-plastic wave evolution leads to enhanced precursor attenuation in thin specimens, but not in thicker ones. Inclusion of dislocation nucleation at subgrain boundaries indicates that a relatively low concentration of subgrain boundaries ( 2/mm) and nucleation density (10"-10 m ) is sufficient to obtain predicted precursor decay rates which are comparable to those obtained from the experiments. These experiments are only slightly above the threshold necessary to produce enhanced elastic-precursor decay. [Pg.229]

Short-time Brownian motion was simulated and compared with experiments [108]. The structural evolution and dynamics [109] and the translational and bond-orientational order [110] were simulated with Brownian dynamics (BD) for dense binary colloidal mixtures. The short-time dynamics was investigated through the velocity autocorrelation function [111] and an algebraic decay of velocity fluctuation in a confined liquid was found [112]. Dissipative particle dynamics [113] is an attempt to bridge the gap between atomistic and mesoscopic simulation. Colloidal adsorption was simulated with BD [114]. The hydrodynamic forces, usually friction forces, are found to be able to enhance the self-diffusion of colloidal particles [115]. A novel MC approach to the dynamics of fluids was proposed in Ref. 116. Spinodal decomposition [117] in binary fluids was simulated. BD simulations for hard spherocylinders in the isotropic [118] and in the nematic phase [119] were done. A two-site Yukawa system [120] was studied with... [Pg.765]

Here kB is the Boltzmann s constant, A represents a normalization factor, W, and W2 are the activation energies for a thermally enhanced decay of the photoin-duced states, E is the temperature-independent part of the decay factor, and B represents the relative weight of the HVaclivalcd process. [Pg.153]

Pulse techniques, coupled with the observation of the decay of enhancement (Atkins et al., 1970a, b Glarum and Marshall, 1970 Smaller etal., 1971) constitute the most sensitive procedure for detecting CIDEP. Both net and multiplet polarization have been described. As with CIDNP, the former is believed to arise essentially from the Zeeman interaction and the latter from the hyperfine term. Qualitative rules analogous to Kaptein s rules should be capable of development. [Pg.121]

The process of exponential multiplication just described produces a rapid decay of the FID and the production of broad lines suppressing the decay of the FID gives narrow lines and better resolution, with increased noise level. An alternative approach to resolution enhancement is to reduce the intensity of the earlier part of the FID. Ideally, we should use a function that reduces the early part of the FID, to give sharper lines, as well as reduces the tail of the FID, to give a better signal-to-noise ratio. [Pg.57]

Matched filter The multiplication of the free induction decay with a sensitivity enhancement function that matches exactly the decay of the raw signal. This results in enhancement of resolution, but broadens the Lorentzian line by a factor of 2 and a Gaussian line by a factor of 2.5. [Pg.416]


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Decay rate, metal-enhanced fluorescence, spectral

Free induction decay resolution enhancement

Metal-enhanced fluorescence decay process

Nonradiative decay enhancement

Radiative decay rate enhancement

Radiative decay rate enhancement mechanisms

Radiative decay rate local field enhancement

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