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Low-frequency, effect

Fig. 4) is physically more reasonable. As a practical matter, as k is increased, the calculation becomes increasingly unreliable because of the severely truncated basis set. The important point is that inclusion of a low frequency effective solvent mode can nicely rationalize the observed characteristics of the C T ion. Similar improvements may be anticipated in analyzing intervalence bands in other systems. [Pg.287]

Wave energy converters will be among the least environmentally harmful energy sources with minimal chemical and shipping hazard risk and zero visual impact for offshore devices (although there are some with shoreline-based devices). There are, however, as yet unconfirmed suggestions of low-frequency effects on marine mammals. [Pg.2641]

As already mentioned, the higher-frequency noise is more strongly amplified by differentiation than the low-frequency effective signal. In order to avoid artifacts it is by all means essential to eliminate this interference with the help of analog or digital methods. [Pg.113]

First, the eddy current density is damped while penetrating into the conductor (penetration effect). Here the frequency dependence of the penetration depth implies that for deep lying cracks low frequencies must be used for obtaining a sufficient current density in the vicinity of the crack. Secondly, due to the induction law the induced current density at the surface jco is diminished when using lower frequencies. Therefore, in total, there is a certain excitation frequency which results in a maximum response field from the crack. [Pg.257]

The frequency correlation lowers environmental disturbances. The correlation provides an output proportional to the content of Aa at the reference signal fundamental frequency, the phase conelation gives the sign of Aa. Where the stress gradients are very steep in materials of high thermal conductivity being loaded at low frequencies, the SPATE signals are attenuated and a correction factor has to be introduced to take into account this effect. [Pg.410]

In light of tire tlieory presented above one can understand tliat tire rate of energy delivery to an acceptor site will be modified tlirough tire influence of nuclear motions on tire mutual orientations and distances between donors and acceptors. One aspect is tire fact tliat ultrafast excitation of tire donor pool can lead to collective motion in tire excited donor wavepacket on tire potential surface of tire excited electronic state. Anotlier type of collective nuclear motion, which can also contribute to such observations, relates to tire low-frequency vibrations of tire matrix stmcture in which tire chromophores are embedded, as for example a protein backbone. In tire latter case tire matrix vibration effectively causes a collective motion of tire chromophores togetlier, witliout direct involvement on tire wavepacket motions of individual cliromophores. For all such reasons, nuclear motions cannot in general be neglected. In tliis connection it is notable tliat observations in protein complexes of low-frequency modes in tlie... [Pg.3027]

Since the stochastic Langevin force mimics collisions among solvent molecules and the biomolecule (the solute), the characteristic vibrational frequencies of a molecule in vacuum are dampened. In particular, the low-frequency vibrational modes are overdamped, and various correlation functions are smoothed (see Case [35] for a review and further references). The magnitude of such disturbances with respect to Newtonian behavior depends on 7, as can be seen from Fig. 8 showing computed spectral densities of the protein BPTI for three 7 values. Overall, this effect can certainly alter the dynamics of a system, and it remains to study these consequences in connection with biomolecular dynamics. [Pg.234]

The dielectric constant (permittivity) tabulated is the relative dielectric constant, which is the ratio of the actual electric displacement to the electric field strength when an external field is applied to the substance, which is the ratio of the actual dielectric constant to the dielectric constant of a vacuum. The table gives the static dielectric constant e, measured in static fields or at relatively low frequencies where no relaxation effects occur. [Pg.464]

In air, PTFE has a damage threshold of 200—700 Gy (2 x 10 — 7 x 10 rad) and retains 50% of initial tensile strength after a dose of 10" Gy (1 Mrad), 40% of initial tensile strength after a dose of 10 Gy (10 lad), and ultimate elongation of 100% or more for doses up to 2—5 kGy (2 X 10 — 5 X 10 rad). During irradiation, resistivity decreases, whereas the dielectric constant and the dissipation factor increase. After irradiation, these properties tend to return to their preexposure values. Dielectric properties at high frequency are less sensitive to radiation than are properties at low frequency. Radiation has veryHtde effect on dielectric strength (86). [Pg.352]

Materials for Electrooptic Modulation. The fundamental phenomenon of Pockel s effect is a phase change, A( ), of a light beam in response to a low frequency electric field of voltage, V. Relevant relationships for coUinear electrical and optical field propagation are as foUows (1 6) ... [Pg.134]

The zinc is normally melted in a gas, oU, or coal-fired reverberatory furnace with a capacity up to 100 tons or in a low frequency induction furnace with a capacity of a few tons. The more highly aUoyed compositions are more effectively melted and mixed in low frequency induction furnaces. The furnace must be refractory-lined to eliminate iron pickup by the molten metal. The metal temperature is maintained below 500°C to minimize loss by oxidation. A ladle is used to transfer the metal for casting into molds the pouring temperature is usuaUy ca 440°C. Zinc scrap is not generaUy suitable for remelting because it may contain undesirable impurities. [Pg.414]

The operating schedule of a gas turbine produces low-frequency thermal fatigue. The number of starts per hours of operating time directly affects the hfe of the hot sections (combustor, turbine nozzles, and blades). The life reduction effect of the number of starts on a combustor liner could be as high as 230 hours/start and on the turbine nozzles as high as 180 hours/start. The effect of full load trips can be nearly 2-3 times as great ... [Pg.2519]

In another promising method, based on the effective Hamiltonian theory used in quantum chemistry [19], the protein is divided into blocks that comprise one or more residues. The Hessian is then projected into the subspace defined by the rigid-body motions of these blocks. The resulting low frequency modes are then perturbed by the higher... [Pg.157]


See other pages where Low-frequency, effect is mentioned: [Pg.280]    [Pg.76]    [Pg.323]    [Pg.21]    [Pg.306]    [Pg.295]    [Pg.134]    [Pg.137]    [Pg.1740]    [Pg.91]    [Pg.528]    [Pg.428]    [Pg.280]    [Pg.76]    [Pg.323]    [Pg.21]    [Pg.306]    [Pg.295]    [Pg.134]    [Pg.137]    [Pg.1740]    [Pg.91]    [Pg.528]    [Pg.428]    [Pg.15]    [Pg.309]    [Pg.235]    [Pg.80]    [Pg.1150]    [Pg.1561]    [Pg.1570]    [Pg.511]    [Pg.7]    [Pg.311]    [Pg.190]    [Pg.375]    [Pg.316]    [Pg.317]    [Pg.319]    [Pg.337]    [Pg.129]    [Pg.134]    [Pg.499]    [Pg.353]    [Pg.315]    [Pg.340]    [Pg.481]    [Pg.2012]    [Pg.159]   


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