Frequency. Curve

Master curves can be used to predict creep resistance, embrittlement, and other property changes over time at a given temperature, or the time it takes for the modulus or some other parameter to reach a critical value. For example, a mbber hose may burst or crack if its modulus exceeds a certain level, or an elastomeric mount may fail if creep is excessive. The time it takes to reach the critical value at a given temperature can be deduced from the master curve. Frequency-based master curves can be used to predict impact behavior or the damping abiUty of materials being considered for sound or vibration deadening. The theory, constmction, and use of master curves have been discussed (145,242,271,277,278,299,300). 

Figure 1.6. Size distribution curve — frequency basis...

Fig. 13. Mott-Schottky plot for a singlecrystal thin-film electrode in 0.5 M H2SO4. Experimental curves, frequency/Hz (1) 21,544, (2) 10,000, (4) 4642, (5) 2154, (6) 1000, (7) 215 (3) calculated curve for Ccaic (discussed in section 5.3, below). Potential vs. Ag/AgCl electrode [78],...

Scanning force spectroscopy (SFS) Force-distance curves Amplitude-distance curves Phase-distance curves Frequency-distance curves - Kelvin probe spectroscopy - Scanning capacitance spectroscopy Full-resonance spectroscopy (FRS) AFAM resonance spectroscopy (AFAM-RS) Scanning spreading resistance spectroscopy (SSRS)... 

The standard way of reporting the results from QRAs/PRAs is to present calculated frequencies (expected values) and probabilities, for example expressed by PEL (Potential Loss of Life) values, FAR (Fatal Accident Rates) values, IR (Individual Risk) values and F-N-curves (Frequency-Nmnber of fatalities). These risk indices form a risk picture, which constitutes the basis for the risk evaluation, to determine the... 

Figure 2.7 shows the concentration dependence of the perpendicular component of the electrical conductivity for two nematic mixtures, A (based on azoxy-compounds) and the Schiff-based mixture B, doped with ionic impurities tetrabutylammonium picrat (TBAP), tetrabutylammonium bromide (TBAB), acceptor impurities tetracyanoethylene (TCE), 2,3-dichloro-5,6-dicyanobenxoquinone (DCDCBQ), tetracyanoquinone-dimethane (TC-QDM), and donor impurity p-phenylenediamine (PDA). Measurements are given for the ohmic part of the current-voltage curves (frequency 1 kHz and cell thickness 100 /xm). The characteristic dependence of a on concentration O oc where c = N/ up/M, predicted for the simple ionization-recombination process discussed, is only observed for ionic impurities. Here the relationship K /Kr can also be determined if we assign a value to the... 

Figure 11 In the right part of the figure is shown the acoustic dispersion curve (frequency v versus wave vector q) for a linear monoatomic lattice. To the left is illustrated the densities of states, D(i>), for the dispersion curve.

Figure 5. Experimental (A) and calculated (B) current-potential curves and complex impedance diagrams at the corresponding points labelled on 1(E) curves (Frequency in Hz) (Johnson-Matthey iron, 1M sulfate, pH = 5, 25°C). Numerical simulation (B) according to the reaction mechanism (36). From ref [61],...

Force-distance curves Amplitude-distance curves Phase-distance curves Frequency-distance curves... 

Dispersion curve Frequencies (energies) of the permitted excitations of a system plotted as a function of their momenta (wave vectors). 

Experimental (a) and calculated (b) current-potential curves and impedance diagrams for a Fe-7Cr alloy (IRSID, France), 1M H2SO4, 25°C. Impedance diagrams at the corresponding polarization points on the 7(E) curve. Frequency in Hertz. Simulations according to the reaction mechanism (3.52). (From Keddam, M. et al., Electrochim. Acta, 31,1147,1986.)... 

By increasing the probe diameter, we bring down tlie impedance point along the impedance curve with the same way as the electrical frequency or conductivity. We will describe only one type of probes, namely, the probe with ferritic circular section that we could qualify as punctual with an optimal sensibility. In order to satisfy these conditions, tests will be made to confirm these results by ... 

All described sensor probes scan an edge of the same material to get the characteristic step response of each system. The derivation of this curve (see eq.(4) ) causes the impulse responses. The measurement frequency is 100 kHz, the distance between sensor and structure 0. Chapter 4.2.1. and 4.2.2. compare several sensors and measurement methods and show the importance of the impulse response for the comparison. 

The thermographic activity on the pressure vessel was carried out considering a part of it because of the axial symmetry. Three different partially overlapping area were inspected since it was optically impossible to scan the curved surface of the pressure vessel by a single sweep. The selected areas are shown in fig.7 and the correspondent positions of the thermographic scan unit are also illustrated. The tests were performed with a load frequency of 2, 5 and 10 Hz. 

The fitting parameters in the transfomi method are properties related to the two potential energy surfaces that define die electronic resonance. These curves are obtained when the two hypersurfaces are cut along theyth nomial mode coordinate. In order of increasing theoretical sophistication these properties are (i) the relative position of their minima (often called the displacement parameters), (ii) the force constant of the vibration (its frequency), (iii) nuclear coordinate dependence of the electronic transition moment and (iv) the issue of mode mixing upon excitation—known as the Duschinsky effect—requiring a multidimensional approach. 

The sharpness of the frequency response of a resonant system is conunonly described by a factor of merit, called the quality factor, Q=v/Av. It may be obtained from a measurement of the frill width at half maxuuum Av, of the resonator frequency response curve obtained from a frequency sweep covering the resonance. The sensitivity of a system (proportional to the inverse of tlie minimum detectable number of paramagnetic centres in an EPR cavity) critically depends on the quality factor... 

Many groups are now trying to fit frequency shift curves in order to understand the imaging mechanism, calculate the minimum tip-sample separation and obtain some chemical sensitivity (quantitative infonuation on the tip-sample interaction). The most conunon methods appear to be perturbation theory for considering the lever dynamics [103], and quantum mechanical simulations to characterize the tip-surface interactions [104]. Results indicate that the... 

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