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Shift and phase

A shift or translation of f(r) by results in a modulation of the Fourier coefficients by exp(-ycofo). Without shift f(r) is transformed into F(fo). After a shift by tQ, fit - tg) is transformed into exp(-ja)tQ) F( n), which results in a modulation (by a cosine or sine wave) of the Fourier coefficients. The frequency cotg of the [Pg.528]

The phase spectrum 0(n) is defined as 0(n) = arctan(A(n)/B(n)). One can prove that for a symmetrical peak the ratio of the real and imaginary coefficients is constant, which means that all cosine and sine functions are in phase. It is important to note that the Fourier coefficients A(n) and B(n) can be regenerated from the power spectrum P(n) using the phase information. Phase information can be applied to distinguish frequencies corresponding to the signal and noise, because the phases of the noise frequencies randomly oscillate. [Pg.529]


In a relatively more recent study, Tarasov et al. used and SSNMR experiments in 2010 to investigate the Knight shifts and phase transition in TiD,c (x= 1.92, 1.98, 2.0) [96]. The authors were investigating the specific origins behind the composition-dependent (i.e., x-dependent) phase transition temperature, and SSNMR experiments were a nat-... [Pg.33]

Laser Doppler Velocimetry (LDV) (Joshi et al. 2001) and PDA (Schafer et al. 2000) are optical techniques that have been used to determine BSDs, gas hold-up and flow patterns. Detectors observe the Doppler shift and phase difference when bubbles pass through the volume of the intersection of two laser beams. Doppler effect is related to the velocities of bubbles and the phase difference is related to the sizes of bubbles. Particle Image Velocimetry (PIV)... [Pg.774]

DOSY NMR experiments are popular for analysing diffusional properties of mixtures. Quality of the results is affected by experimental factors such as baseline drift, peak shift and phase shift. Huo et al proposed a series of pre-processing operations to reduce the experimental distortions, including baseline correction and reference deconvolution to remove frequency and phase shifts. The corrected data can be successfully analysed with a combination of multivariate curve resolution with non-linear least square regression. [Pg.346]

Phase Doppler [43,44,45,46, 47,481 Scattering frequency shift and phase delay Sizing, counting, flow velocity study Flow... [Pg.60]

According to some remarks concerning the physical interaction between the incident ultrasonic wavelet and the defects [4-6], we consider that an Ascan signal, may be described as a weighted sum of few delayed and phase-shifted replicas of the ultrasonic incident wavelet j(r). We can express this mathematically as ... [Pg.174]

The aim of the experiment was to study the transmission of a signal through the weld and to measure the frequency and phase dependencies of parameters of acoustic signals from the angle of incidence and beam path within the weld volume. One of the shift of the spectral characteristics the signal is shown in Figure 4(a,b). [Pg.732]

The relationship between mean squared phase shift and mean squared displacement can be modelled in a simple way as follows This motion is mediated by small, random jumps in position occurring with a mean interval ij. If the jump size in the gradient direction is e, then after n jumps at time the displacement of a spin is... [Pg.1540]

The END trajectories for the simultaneous dynamics of classical nuclei and quantum electrons will yield deflection functions. For collision processes with nonspherical targets and projectiles, one obtains one deflection function per orientation, which in turn yields the semiclassical phase shift and thus the scattering amplitude and the semiclassical differential cross-section... [Pg.236]

After a suitable number of pulses have been acquired, the time-domain spectmm is transformed into a frequency-domain spectmm and phased so that the base line of the spectmm is fiat and the peaks all fall on the same (positive) side of the base line. Information obtainable from this spectmm includes chemical shifts, coupling constants, and integrated peak areas. [Pg.402]

Molecules vibrate at fundamental frequencies that are usually in the mid-infrared. Some overtone and combination transitions occur at shorter wavelengths. Because infrared photons have enough energy to excite rotational motions also, the ir spectmm of a gas consists of rovibrational bands in which each vibrational transition is accompanied by numerous simultaneous rotational transitions. In condensed phases the rotational stmcture is suppressed, but the vibrational frequencies remain highly specific, and information on the molecular environment can often be deduced from hnewidths, frequency shifts, and additional spectral stmcture owing to phonon (thermal acoustic mode) and lattice effects. [Pg.311]

Vibrational spectra including Raman data of 3,3-dimethyldiaziridine and its hexadeutero compound were recorded in the gas phase and in the crystalline state. Assuming C2 symmetry and employing isotopic shifts and comparison with azetidine, a classification of bands which regarded 33 normal modes could be given (75SA(A)1509). [Pg.202]

The auto-synchronizing relay monitors AV, Af and phase shift (Ad), between the two voltage phasors. In other words it monitors the residual voltage, It also ensures that G is slightly ahead of the existing source at the instant of synchronization. [Pg.526]

The schematic and Bode plot for the single-pole method of compensation are given in Figure B-16. At dc it exhibits the full open-loop gain of the op amp, and its gain drops at -20dB/decade from dc. It also has a constant -270 degree phase shift. Any phase shift contributed by the control-to-output characteristic... [Pg.208]

Tamayo, J. and Garcia, R., Relationship between phase shift and energy dissipation in tapping-mode scanning force microscopy. Appl Phys. Lett., 73(20), 2926-2928 (1998). Gotsmann, B., Seidel, C., Anezykowski, B. and Fuchs, H., Conservative and dissipative tip-sample interaction forces probed with dynamic AFM. Phys. Rev. B Condens. Matter, 60, 11051-11061 (1999). [Pg.217]

Resistivity. The 2-MHz LWD amplitude and phase-shift resistivity logs match the wireline deep and medium induction very well. Excellent results are obtained when the invasion is not severe (less than 40 in. in diameter) and in formations 20 f2 m or less. [Pg.1078]

Important balancing techniques and concepts to be discussed in the sections to follow include in-place balancing, single-plane versus two-plane balancing, precision balancing, techniques that make use of a phase shift, and balancing standards. [Pg.939]


See other pages where Shift and phase is mentioned: [Pg.528]    [Pg.528]    [Pg.258]    [Pg.316]    [Pg.320]    [Pg.1541]    [Pg.1662]    [Pg.1662]    [Pg.1883]    [Pg.1989]    [Pg.1990]    [Pg.2033]    [Pg.134]    [Pg.163]    [Pg.326]    [Pg.409]    [Pg.56]    [Pg.129]    [Pg.426]    [Pg.510]    [Pg.334]    [Pg.522]    [Pg.238]    [Pg.130]    [Pg.793]    [Pg.10]    [Pg.142]    [Pg.189]    [Pg.196]    [Pg.222]    [Pg.250]    [Pg.203]    [Pg.32]    [Pg.687]    [Pg.157]   


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