Square wave rectangular

Sinusoidal excitation provides only one harmonic at the modulation frequency. In contrast, pulsed light provides a large number of harmonics of the excitation repetition frequency. The harmonic content, the number of harmonics and their amplitude, is determined by the pulse width and shape.(25) For example, a train of infinitely short pulses provides an infinite number of harmonics all with equal amplitude. A square wave provides only three modulation frequencies with sufficient amplitude to be usable. Equation (9.74) gives the harmonic content of a train of rectangular pulses R(t) of D duty cycle (pulse width divided by period) and RP peak value ... 

The experiments of Eigen and DeMaeyer (1955) employed a square-wave Wheatstone Bridge. A more recent version (Rampton et al., 1967) of this instrument is shown in Fig. 3-7. A rectangular, approximately 50 kV, pulse is applied to a two-platinum-clcctrode sample cell that is one arm of an asym-... 

The pressure response to the voliune perturbation was recorded with a high-accuracy differential Baratron pressure transducer (MKS 698A11TRC) (Eq. 10) at each frequency over three to five square-wave cycles (256 pressure readings per cycle) after the periodic steady-state had been established. The isotherm describing the equilibrium sorption conditions can be linear or curved. However, the horizontal region of a rectangular isotherm cannot be used as there is no sorption/desorption following the square-wave modulation of the equilibrium volume. 

Pulsating overpotential consists of a periodic repetition of overpotential pulses of different shapes. Square-wave PO is defined in the same way as PC except that the overpotential pulsates between the amplitude value and zero instead of current density. Non-rectangular pulsating overpotential is defined by the amplitude of the overpotential, rj, frequency, and overpotential waveform [7]. 

To reduce the effect of double-layer capacitance, the same technique is often used as in the case of some voltammetric measurements. After applying a square wave or other rectangular input voltage, the current response is sampled only during a short interval at the end of each voltage pulse, when the capacitance portion of the current is reduced almost to a value of zero following an exponential time-dependence with the exponent — t/RCo (R is the solution resistance and Co the differential capacitance of the double layer). 

Square wave A square or rectangular-shaped periodic wave that alternately assumes two fixed values for equal lengths of time, the transition being neghgible in comparison with the duration of each fixed value. 

The hydrodynamically modulated RRDE (HMRRDE) allows the measurement of small currents on a large background (Haupt and Strehblow, 1987b). The modulated current response due to a sinusoidal, square wave, or rectangular variation of the rota-... 

Example The FT of a continuous rectangular wave (shown in the upper left of Figure 15.1) is relatively easy to derive. We begin with the general case of arbitrary on-time but will later consider the special case of a square-wave (T = Tq/2,... 

Example Feldman (2007) does this problem in detail (his Example 1) for the continuous rectangular pulse - shown in the upper right quadrant of Figure 15.1. Feldman s example has the period M = 11, and the pulse is on for five data points - we will carry that value in the following derivation simply as 5 , but it will be clear how to generalize this if we so desire. Note that this is not the common 50% duty cycle square wave. 

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