Modulation of the signal

As is evident from Fig. 5.26, we can have either a sinusoidal modulation or a cosinusoidal modulation of the signals, depending on whether the two 90° pulses have the same phase or different phases. In Fig. 5.26A, both pulses have the same phase. This means that in the first period, the magnetization vector precesses in the x 31 -plane, so if it has processed by... 

Treffer s model system consists of signal power P (in watts) falling on the input aperture of the modulator (i.e., the spectrophotometer) that modulates the input power as a function of time by a factor M(t) such that 0 < M(t) < 1. The modulation function M(t) is not the modulation of the signal due to chopping but modulation of the signal due to scanning. The modulated signal falls on a detector with responsivity R (in volts per watt) (Kruse et al., 1962 Stewart, 1970) and flat frequency response. The idealized instantaneous... 

Fig. 2.50. Generation of /-resolved two-dimensional 13C NMR spectra (a) flux diagram (b) /-modulation of Cl l doublets, CH2 triplets and CH3 quartets during evolution, vector diagrams in the x y plane and cosine curves described by the signal maxima (c) series of 13C NMR spectra of CHn groups with t1 dependent /-modulation of the signal amplitudes (d) series of /-resolved two-dimensional 13C NMR spectra formethine, methylene and methyl carbon atoms, stacked plots and contour plots (e).

The excited iodine atom produced in reaction (18a) absorbs one or two photons to yield the I+ ion. The Xe pressure in the third harmonic cell is adjusted so that the one-and three-photon signals are approximately equal. Variation of the H2 pressure in the phase-tuning cell produces the sinusoidal variation of the ion signals shown in Fig. 6. Evident in this figure is a phase lag of 150° between the two products, HI+ and I. Also shown is modulation of the signal produced by photoionization of H2S, which provides a reference phase for the HI+ and I+ signals. 

As a consequence of the extremely high mass transport rates attainable at UMEs, HM effects at vibrating UMEs are normally small. However when the electrode is in close proximity to a surface these effects can be greatly enhanced. Although the modulation of the signal is not hydrodyn-... 

Signal transduction can be analyzed by currently available proteomic technologies because signaling pathways contain enzymes, which modify high-abundance proteins other than those of the pathway. Thus, modulation of the signaling through a pathway will produce a "footprint" in the proteome that is characteristic of a specific cell phenotype (Resing, 2002). 

Figure 4. Schematic illustration of the steps in producing a 2D-NMR spectrum a) raw tl/t2 data, b) after FT with respect to t2, c) tl modulation of the signal intensities at the shifts ofpeaks a and b in (b), and d) final spectrum after FT with respect to both tl and t2.

Figure 10.4 The multivibrator consists of a RC network and 2 inverters, while the frequency modulation of the signal is achieved by the variations in the load of the first inverter which is the sensor array...

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