Pulsed effect

Weekman and Myers (W2) examined the fluid-flow characteristics of cocurrent downward flow of gas and liquid. The pulsing effect first noted by Larkins et al. was also observed in this work. Pressure-drop data could be correlated satisfactorily by a relation similar to those used for two-phase flow in pipes. Surface-active agents were observed to have a pronounced influence upon flow regime transition and pressure drop. 

Voltage-pulsed AP analysis of resistive materials is difficult, since they do not transmit high-voltage pulses effectively. In the case of semiconducting materials there is the further problem of their brittleness, so that the mechanical shock due to the voltage pulse often causes specimen fracture. The pulsed laser atom probe (PLAP) is more effective for these materials. 

The RFDR experiment (Fig. 2b), here serving to illustrate the incorporation of finite rf pulse effects into the design or refinement process, was first introduced by Griffin,... 

Although the mechanisms of electroporation, electrofusion, and electroinsertion are not known, biophysical data suggest that the primary field pulse effect is interfacial polarization by ion accumulation at the membrane surfaces. The resulting transmembrane electric field causes rearrangements of the lipids such that pores are formed1718. Electropores anneal slowly (over a period of minutes) when the pulse is switched off. 

The general arrangement of an hplc system is fairly simple, as shown in Fig. 9.17. Solvent is pumped from a reservoir through a piston pump which controls the flow rate. From the pump the solvent passes through a pulse damper which removes some of the pulsing effect generated in the pump and also acts as a pressure regulator. In between the pulse damper and the column there is an injection valve which allows the sample to be introduced into the solvent stream. 

In a system consisting of two coupled spins 1/2, Hartmann-Hahn transfer can be conveniently analyzed based on the one-to-one correspondence between the evolution of the density operator in the zero-quantum space that is spanned by the operators (ZQ),, (ZQ)y, and (ZQ) [Eq. (14)] and the magnetization trajectory of a single, uncoupled spin in the usual rotating frame (Muller and Ernst, 1979 Chingas et al., 1981 Kadkhokaei et al., 1991 see Fig. 2). This equivalence can be used for the construction of zero-quantum analogs of well-known composite pulses. Effective phase shifts of the zero-quantum field can be implemented by short periods of precession about the z axis of the zero-quantum frame... 

As was shown in articles, the preparatory pulse effect is "forgotten" by the spin system after times of abouf several T2e and, consequently, the spin-locking effect vanishes at the same time. If in Equation (43) we set pg = 0, the result will be that "forgetting" the preparatory pulse leads to the disappearance of fhe differences between MW-4 and SORC. 

Over the small potential range between forward and reverse pulses, the interfacial capacity is normally constant, and thus calculation of the difference between responses from backward and forward pulses effectively annuls the capacitive contributions. It is not necessary to wait... 

Pulse effect higher load, approximately separation efficiency doubled. 

In contrast to technique A the pulse effect on the protoplasts collected as "pearl necklaces" can be observed and documented by photos or by a video camera. The high pulse causes oscillations in field direction during the first second followed by membrane flattening between the cell (Figure 5). 

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