Pulse pressure trace

Figure 3.63 Superposition of representataive oscilloscope pressure traces at locations 2 and 3 for compression and rarefaction pressure pulses in low-void-fraction steam-water mixtures. (From Grolmes and Fauske, 1969. Copyright 1969 by Elsevier Science SA, Lausanne, Switzerland. Reprinted with permission.)...

FIGURE 3 7. A pressure trace as a diagnostic aid. (a) A properly performing solvent delivery system, (b) A pressure dip probably due to a bubble being pumped. (c) An improperly pulsing solvent delivery system which probably has bad check valves. Note that the relative pulsation for a good and bad solvent delivery system must be determined for each system. Each solvent delivery system will be somewhat different. 

In the first test run the two pressure traces represent measurements at inlet and outlet of the boiler. Both traces show the characteristic pressure pulses obtained in the work of King. The first, second, and fourth pulses detected at the sodium inlet appear the strongest, thereby indicating the reaction producing these pulses was nearest to this pressure detector. The third pulse is due to a reaction taking place nearer the sodium outlet. These pressure pulses were produced by nonuniform reaction effects similar to those previously discussed. The pressures obtained at the inlet and outlet are different, indicating that appreciable plugging of the tube took place. When the unit was disassembled, a mixture of sodium, mercury, and sodium-water reaction products was found in the tube. 

RGURE 14.2 (a) Theoretical and (b) experimental pressure trace in a pulse combus-... 

Fig. 2.2 (a) Theoretical and (b) experimental pressure trace in a pulse combustor. A air and fuel enter the combustion chamber B fresh charge ignited, pressure rises as combustion gases heat up, air and fuel inflow are stopped ... 

Care is needed in applying the unsteady state pulse technique to a Wicke-Kallenbach cell in order to obtain values for effective diffusion coefficients. For sufficiently small concentrations, where the trace component is of higher diffusivity than the carrier, the commonly used isobaric model is adequate for defining the transport parameters if sufficiently short pulses are used. However, where adsorption of either carrier or trace component occurs or wheipe the trace is of lower diffusivity, then the induced total pressure gradients cause the fluxes to show unusual behaviour and may require analysis by a non-isobaric model. 

Daescher [87] describes a method using a set of tared sieves mounted on a special funnel held in a filter flask. 1 to 3 g of powder are placed on the top sieve and washed through each sieve in turn with a suitable polar liquid or hydrocarbon containing a trace of dispersant. At the same time, alternate pulses of pressure and suction are applied to the filter flask. This pulsating action orientates the particles in such a way as to speed up the sieving action. A full analysis can be completed in less than an hour. 

In an extensive clinical study of 159 people, pulse, blood pressure, and electrocardiograms were monitored in 16 of the individuals taking about 3 mg/kg/day (Simkins 1937a, 1937b). No abnormal electrocardiographic tracings were found, but bradycardia was observed in two cases. Blood pressure was reduced in 10 formerly hypertensive patients, but no blood pressure changes were found in normotensive individuals. The reasons for the fall in blood pressure in the hypertensive... 

Figure 6.15 shows that the transmitted light is a function of the pressure for recombination of photodissociated ligands in a reaction of an iron porphyrin with CO. The laser pulses had energies of about 3 mJ, and a few hundred laser shots were summed for each trace. These intensities have to be converted to absorbance signals. The data give AF = —19.3 0.4 cm mol F... 

A resonant charging supply enabling 10-kilowatt peak burst power for 100 pulses is under development. Typical output into the corona chamber is shown in Fig. 5.5. The pulse is the second one of the two pulse bursts. The working gas in this case was air at atmospheric pressure. Noise on the current trace is typical of corona discharges and is a consequence of the large number of streamers carrying varying amount of current. 

Figure 3. Oscilloscope traces of the electron decay in pulse-irradiated air at pressures of 6.0 and 36 torr. Electron concentration in arbitrary units. Time scale refers to heavy vertical divisions...

When the dye in the thin water layer is laser pulsed, its proton is rapidly ejected and, after rapid relaxation to ground state, an ion pair H+ and 4>0 is formed. The strong absorption of the 4>0 anion (at 450 nm) fades rapidly (within a few microseconds) due to its reaction with the proton, and the system relaxes to its initial prepulse state. Typical traces are shown in Figure 1. The two traces correspond to recombination in unstressed vesicles, where the width of the water layer is 25 A, and under strong osmotic pressure (applied by sucrose), which squeezes the water layer to 10 A (7). Both signals exhibit a rise time, unresolved at that time frame, followed by well-resolved relaxation. 

A typical emission trace for XeF is shown in Figure 5a, for 500 Torr of xenon and 0.50 Torr of SF. This curve has several components a X-ray signal, dimer rare gas fluorescence and ionic recombination formed exciplex fluorescence. The X-ray signal followed the time profile of the 3 ns. electron pulse, and was typically only a few percent of the total emission signal. The first emission peak was also observed in irradiated pure xenon, at all wavelengths across and outside the XeF emission spectrum, and was therefore assigned to the broad xenon dimer, Xe2 fluorescence. The decay of the dimer fluorescence was typically complete within several hundred nanoseconds, and its intensity varied greatly with the xenon pressure. The second peak in the emission curve was dose-dependent, and only observed across the known XeF ... 

Stagnant solvent in parts of the HPLC instrument can cause extra peaks. The pressure pulse from the injection may cause a smaU quantity of the stagnant solvent to enter the mobile-phase stream and ultimately create additional peaks. This is one of the more diflScuIt conditions to trace and to eliminate. 

FIGURE 8.21 Premature ventricular contraction following ultrasound irradiation, during diastole, of the in vivo frog heart. The top trace is aortic pressure and below is the EGG. A lithotripter pulse of 20 MPa, 5 msec duration, is delivered at the vertical arrow. (Adapted from Dalecki, D., Raeman, C.H., Child, S.Z., and Carstensen, E.L. 1997. Ultrasound Med. BioL 23 275-285.)... 

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