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Oscillation indicator

Here scalar order parameter, has the interpretation of a normalized difference between the oil and water concentrations go is the strength of surfactant and /o is the parameter describing the stability of the microemulsion and is proportional to the chemical potential of the surfactant. The constant go is solely responsible for the creation of internal surfaces in the model. The microemulsion or the lamellar phase forms only when go is negative. The function/(<))) is the bulk free energy and describes the coexistence of the pure water phase (4> = —1), pure oil phase (4> = 1), and microemulsion (< ) = 0), provided that/o = 0 (in the mean-held approximation). One can easily calculate the correlation function (4>(r)(0)) — (4>(r) (4>(0)) in various bulk homogeneous phases. In the microemulsion this function oscillates, indicating local correlations between water-rich and oil-rich domains. In the pure water or oil phases it should decay monotonically to zero. This does occur, provided that g2 > 4 /TT/o — go- Because of the < ), —<(> (oil-water) symmetry of the model, the interface between the oil-rich and water-rich domains is given by... [Pg.161]

We examine the time dependence of the charge transfer P,(t) in Fig. 5a for the wide band and Fig, 5b for the narrow band. Both curves show some oscillation, indicating there can be a series of transfers between the atom and the band. We have used A = 0.1, so the atom is moving slowly and is in the vicinity of the surface for a sufficiently long time for these multiple transfers to occur. The graphs show that the effective interaction time, when transfers take place, is about [ — 4A, 4A] for the narrow band and [ — 2A, 2A] for the wide band. It has been suggested that it is only the outward (r > 0) part of the atom s trajectory which is important for the charge-transfer process, but that is certainly not true for the cases shown in Fig. 5. [Pg.348]

The general form of the energy of the harmonic oscillator indicates that the vibrational energy levels are equally spaced. Due to the vector character of the dipole transition operator, the transition between vibronic energy levels is allowed only if the following selection rule is satisfied ... [Pg.154]

The adsorption site, i.e. the chemisorption position of the adatoms on (within, below) the substrate surface, thanks to the polarisation dependence of SEXAFS. Often a unique assignment can be derived from the analysis of both polarisation dependent bond lengths and relative coordination numbers. The relative, polarisation dependent, amplitudes of the EXAFS oscillations indicate without ambiguity the chemisorption position if such position is the same for all adsorbed atoms. More than one chemisorption site could be present at a time (surface defect sites or just several of the ideal surface sites). If the relative population of the chemisorption sites is of the same order of magnitude, then the analysis of the data becomes difficult, or just impossible. [Pg.98]

The EXAFS spectra for Br" display weak oscillations, indicating either a small coordination number or a large disorder of the coordination bond lengths due to the weak Br -solvent interactions. Some of the spectra display strong multi-electron excitation structures and this structure had to be removed before the EXAFS analysis. The EXAFS oscillations for several typical solutions are given in Fig. 1. In all cases the oscillations for aprotic solutions arc weaker compared to aqueous or protic solutions. Most of the spectra could be analyzed by using a one-shell model, but it is clear that the data for acetic add (4) and t-butyl alcohol (12) can not be adequately analyzed by the one-shell model. [Pg.247]

Comparison with direct count methods for systems of harmonic oscillators indicates that the classical density of states is generally an underestimate. However, it is so convenient to have an explicit formula for the density of states that more accurate semiclassical approximations have been developed. [Pg.38]

Measurements of the frequency of the oscillation indicated that the decrease in inductance resulted in the increase in frequency. As these phenomena are similar to the discharge of a condenser charge through the resistance or the inductance, the capacity of the condenser was evaluated from the values of the resistance, the tail length, and the inductance to be about 200 /x/xf., irrespective of the values of the resistance and the inductance. [Pg.336]

They concluded that the existence of horatian oscillations indicates that the kinetic model of the catalytic system contains equations of higher than second order. [Pg.98]

To determine the resonance frequency of the resonator it is suspended by a fine thread in a vessel containing the medium being studied, and is brought into the field of an oscillator whose frequency is controlled by a variable condenser. When this frequency corresponds to that of the oscillator there is a sudden change of the plate current of the oscillator indicating an absorption of power. In determining high dielectric constants it is frequently desirable to use, as reference, an intermediate liquid whose constant may be found with the aid of equation (9). [Pg.408]

Darakjian et al. (164) computed accurate densities of reactive states for He + H2 - HeH+ + H with 7 = 0. The raw CRP exhibited many rapid oscillations, indicative of narrow trapped-state resonances. By averaging the cumulative reaction probability for... [Pg.371]

Fig. 4.2. Bifurcation diagram as a function of parameter k. The steady-state concentration of substrate, oq, as well as the maximum concentration of substrate in the course of oscillations, indicated. Solid and dashed lines... Fig. 4.2. Bifurcation diagram as a function of parameter k. The steady-state concentration of substrate, oq, as well as the maximum concentration of substrate in the course of oscillations, indicated. Solid and dashed lines...
Fig. 14. Temporal evolution of a transient three-photon ionization signal of decaying Na2K (a) and its emerging fragment NaK (b). The decay time of the excited trimcr corresponds well to the rise time of its diatomic fragment. The superposed oscillations indicate wave packet oscillations in the coherently excited system. Fig. 14. Temporal evolution of a transient three-photon ionization signal of decaying Na2K (a) and its emerging fragment NaK (b). The decay time of the excited trimcr corresponds well to the rise time of its diatomic fragment. The superposed oscillations indicate wave packet oscillations in the coherently excited system.
At this moment, there are other candidates for contributing significantly to the mass of the Universe, mainly the mysterious dark matter. This constitutes the major part of the mass of the Universe. We know very little about it Recently, it turned out that neutrinos undergo what are called oscillations, e.g., an electronic neutrino travels from the Sun and on its way spontaneously changes to a muonic neutrino. The oscillations indicate that the mass of the neutrino is nonzero. According to current estimations, however, it is much smaller than the accuracy of the tritium experiments. [Pg.594]

This is a good classroom demonstration experiment. Hydroquinone stops the oscillations indicating the important role played by the free radicals. In such reactions, auto catalytic production CgHjCHO or CH3CHO has been envisaged as it happens in gas... [Pg.143]

As will be demonstrated in this chapter, the rate at which oscillations occur in a temporal oscillator depends on both inductive and capacitive properties of the oscillator, indicating that there exists a correlation between time and the ability of a system to store more or less energy. It will be... [Pg.348]

Additional experimental data are summarized in Table III in order of increasing flow rate at NTP for the 2% CO, 3% O2 and 1% 1-butene in argon feed mixture. These experimental results in the regions of oscillations indicated that at fixed reactor space time, higher temperatures resulted in period and amplitude decreases for all components of the reacting system. At constant temperature, space time decreases also resulted in period and amplitude decreases. The time-averaged rates of oxidation of both CO and 1-butene increased with temperature and with reduction in space time. Reactor material balances suggested that 1-butene oxidation was essentially complete to CO2 and H2O. [Pg.482]

To examine the temperature dependence of the local properties of water, the fluid layers should be reasonably defined. The first surface layer may be defined in a natural way based on the first density oscillation, which is clearly visible at the density profiles even at high temperatures (see Figs. 44 and 45). Water molecules located in a shell bounded from one side by the van der Waals contact between water and surface ajl- 1.25 A from the surface, where Kz = 0) and by the first minimum in the liquid density distribution at low temperatures from another side (typically about 3.75 A) should be attributed to the surface layer. At low temperatures, the second density oscillation indicates the second layer of water, whose thickness is about 3 A. This oscillation practically disappears at high temperatures, where density changes gradually at the distances r > 5 A from the surface. In case of a smooth density variation, the layer thickness could be chosen to be arbitrarily small. It is convenient to set the thickness of third and subsequent water layers to 3 A. [Pg.81]


See other pages where Oscillation indicator is mentioned: [Pg.412]    [Pg.31]    [Pg.89]    [Pg.482]    [Pg.235]    [Pg.3]    [Pg.130]    [Pg.630]    [Pg.176]    [Pg.357]    [Pg.91]    [Pg.507]    [Pg.34]    [Pg.406]    [Pg.239]    [Pg.565]    [Pg.128]    [Pg.196]    [Pg.494]    [Pg.517]    [Pg.130]    [Pg.138]    [Pg.235]    [Pg.244]    [Pg.684]    [Pg.247]    [Pg.411]    [Pg.45]    [Pg.796]    [Pg.196]    [Pg.344]    [Pg.344]   
See also in sourсe #XX -- [ Pg.344 ]




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