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Kinetic relaxation

Macroscopic Kinetics Relaxations (Such as Synaptic Currents) and Noise...198... [Pg.183]

This transition is a kinetical, relaxational process. The variation of the temperature above Tg is followed by the shift of the equilibrium between free and bonded hydroxyl groups. This shift sets in practically instantly, as the relaxation times x are very small above Tr At the temperatures below Tg the relaxation times are very long and the variation of the temperature in this region is not connected with the change of equilibrium. The fraction of free hydroxyls v at T < Tg is not equal to ve, the equilibrium fraction at this temperature. [Pg.489]

Consider, in general, a set of reaction coordinates rj providing the kinetic relaxation of the system, i.e., all the other degrees of freedom are assumed to be fully equilibrated along the a relaxation. The equations of motion for the i] degrees of freedom when averaging over the ensemble defined by the molecules (typically the solute molecules) within a tiny rj volume (equivalent to a numerical differential) can be approximated as... [Pg.201]

The ion—pair rel20cation process, found at the low frequency side of the spectra is the consequence of the reorientation of ion pairs behaving like dipole molecules. However, the frequency window of ion-pair reorientation generally comprises the frequency range of the kinetic relaxation process of ion-pair formation and dissociation... [Pg.184]

This review has focused on recent research directed toward characterization of the active sites for water-gas shift over magnetite-based catalysts. The reaction can be described by a regenerative mechanism wherein gas phase or weakly adsorbed CO reduces anion sites and steam oxidizes the resultant surface oxygen vacancies. Kinetic relaxation techniques indicate this to be a primary pathway. The sites which participate in this reaction comprise only about 10% of the BET monolayer, and these sites can be titrated using CO/CO2 adsorption at 663 K. In contrast, the total cation site density is effectively titrated with NO at 273 K. In fact, the ratio of the extent of CO/CO2 adsorption to the extent of NO adsorption provides a measure of the fraction of the magnetite surface which is active for water-gas shift. [Pg.336]

This function is the sum of two exponentials, one whose decay rate depends solely on the translational diffusion coefficient and another whose decay rate depends on both the translational diffusion coefficient and the kinetic-relaxation rate 1/rr. The strength of the term containing the kinetic relaxation time depends on the difference between the polarizabilities of the molecule in states 1 and 2, as we surmised in Section (6.1). In most cases the purely diffusive contribution which contains the square of theaverage polarizability increment will contribute much more strongly than the second term. This result should be contrasted with the electrophoretic case in the slow exchange limit [Eq. (6.3.4)]. In the electrophoretic case ka and kb separately appear in the expressions, whereas in the zero field case only the combination tr appears. [Pg.102]

Fig. 8. Rapid-scanning visible spectra showing the changes in the Co(II)E spectral bands during the pre-steady-state and steady-state phases of benzyl alcohol oxidation by NAD at pH 9 (A), pH 4.8 (B, D), and pH 5.6 (C) and 25°. Scanning was carried out as described in the caption to Fig. 5. The pre-steady-state reaction at pH 9.0 (A) occurs in two kinetic relaxations the spectra in A-1 show the changes in both relaxations as the steady state is approached the changes which occur in each relaxation are shown offset in A-2 (the fast relaxation) and A-3 (the slow relaxation), respectively. The time-resolved spectra in (B) and... Fig. 8. Rapid-scanning visible spectra showing the changes in the Co(II)E spectral bands during the pre-steady-state and steady-state phases of benzyl alcohol oxidation by NAD at pH 9 (A), pH 4.8 (B, D), and pH 5.6 (C) and 25°. Scanning was carried out as described in the caption to Fig. 5. The pre-steady-state reaction at pH 9.0 (A) occurs in two kinetic relaxations the spectra in A-1 show the changes in both relaxations as the steady state is approached the changes which occur in each relaxation are shown offset in A-2 (the fast relaxation) and A-3 (the slow relaxation), respectively. The time-resolved spectra in (B) and...
The root. i simply indicates that infinite distances are correlated with infinite time, S2 is the reciprocal of the Debye relaxation time, and 3 is the kinetic relaxation frequency of the system. Depending on the kinetic parameters of the chemical process, the kinetic relaxation frequency can be faster or slower than the Debye frequency of the system. If the kinetic relaxation frequency is much smaller than the Debye mode, it can be determined experimentally by conductance fluctuation analysis. [Pg.105]

The six first case studies deal with the phenomenon of relaxation caused by the dissipation associated with conduction, mainly in the capacitive subvariety as only one woiks in the inductive subvariety with the kinetic relaxation (decelerated motion). Both global and space distributed systems are studied and also free and forced relaxation. [Pg.517]

Contents Introduction. - Basic Concepts of Quantum Electronics. - Physico-Chemical Gas Kinetics. - Relaxation in Nozzle Gas How. - Infrared CO2 Gasd)mamic Laser. -Gasdynamic Lasers with Other Active Medium. - Appendixes. - List of the Most Used Symbols. - References. -Subject Index. [Pg.157]

ION ADSORPTION-DESORPTION KINETICS relaxation times can be expressed as... [Pg.589]

Young RC, Meyer TJ, Whitten DG (1975) Kinetic relaxation measurement of rapid electron transfer reactions by flash photolysis. The conversion of light energy into chemical energy using the Ru(bipy)3 A Ru(bipy)3 couple. J Am Chem Soc 97 4781-4783... [Pg.127]

Relaxation studies could be named physical kinetics but it is clear that the distinction between chemical and physical kine--tics is arbitrary. Chemical kinetics and physical kinetics (relaxation studies) are strongly interconnected domains. Without relaxation, no system would be at equilibrium in a nonsta-tionary world like ours. This remark leads to the conclusion that relaxation phenomena are of fundamental importance and of great generality. [Pg.65]


See other pages where Kinetic relaxation is mentioned: [Pg.25]    [Pg.124]    [Pg.38]    [Pg.201]    [Pg.313]    [Pg.317]    [Pg.318]    [Pg.2]    [Pg.101]    [Pg.595]    [Pg.201]    [Pg.58]    [Pg.134]    [Pg.8]    [Pg.150]    [Pg.184]    [Pg.160]    [Pg.557]    [Pg.56]    [Pg.190]    [Pg.145]   
See also in sourсe #XX -- [ Pg.25 ]

See also in sourсe #XX -- [ Pg.182 ]

See also in sourсe #XX -- [ Pg.403 ]




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Adsorption Relaxation Kinetics

Adsorption kinetics pressure-jump relaxation

Arsenate pressure-jump relaxation kinetics

Chemical kinetics relaxation methods

Chemical reaction rate theory, relaxation kinetics

Confined system relaxation kinetics

Decay kinetics solvent relaxation

Dielectric relaxation kinetic mechanisms

Electrode kinetics relaxation methods

Free volume models relaxation kinetics

General models for adsorption kinetics and relaxations of surfactants

Kinetic Equations for Orientational Relaxation in Depolarized Scattering

Kinetic analysis, relaxation methods

Kinetic equations dielectric relaxation

Kinetic models of structural relaxations in metallic glasses

Kinetic relaxation measurements

Kinetic relaxation process

Kinetic systems relaxation amplitudes

Kinetic systems relaxation spectra

Kinetics interface relaxation

Kinetics of structural relaxation and equilibrium

Kinetics of structure relaxation

Kinetics relaxation methods

Ligand binding reaction relaxation kinetics

Micelle kinetics relaxation time

Mode-Coupling Theory relaxation kinetics

Monotone relaxation kinetics

Nonexponential relaxation kinetics

Physical kinetics relaxation process, time

Potential-relaxation method kinetic theory

Proton-activated, 419 relaxation kinetics

Rate equations relaxation kinetics

Relaxation Derived as an Analogue to First-Order Chemical Kinetics

Relaxation kinetic theories

Relaxation kinetics

Relaxation kinetics

Relaxation kinetics of polarization moments

Relaxation methods adsorption-desorption kinetics

Relaxation methods kinetic isotope effect

Relaxation process formation, kinetics

Relaxation techniques kinetic analysis

Relaxation time adsorption-desorption kinetics

Relaxational kinetic equations

Rotational kinetics and relaxation time

Rotational relaxation kinetic and spectral manifestations

Spin Kinetics Derivation of the Rate Equation for Cross-Relaxation

Temperature-jump relaxation kinetic

Temperature-jump relaxation kinetic studies

The different subjects of adsorption kinetics and relaxations at

Time constant relaxation kinetics

Transient kinetics steady-state, relaxation

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