Wave recorder

It appears that the voltage waves recorded in the EEG represent the summation of synaptic potentials in the apical dendrites of pyramidal cells in the cortex. These cells generate sufficient extracellular current for it to reach, and be recorded from, the cranium and scalp. Although these waves originate from the cortex rather than the SCN, the distinctive REM and non-REM phases of sleep still remain after destruction of the SCN but they then occur randomly over the 24-h cycle. This is a further indication that the SCN is at least partly responsible for setting the overall circadian rhythm of the sleep cycle. 

Seismic techniques, the reflection and refraction of sound or shock waves propagated through the earth, are also used to reveal details of the structure and interrelationship of various layers in the subsurface. The shock or sound waves record densities in the earth s surface that may indicate an oil or gas reservoir. Explosive charges or vibration devices are used to impart the required shock wave. 

The discussion is simplified if electron transfer is assumed to obey the Volmer-Butler law, at least in the potential range of a wave recorded at a given scan rate. Under these conditions, the dimensionless expression of the cathodic trace of the irreversible voltammogram is given by (see Section 6.2.1)... 

To define the possible mechanism of the surface electrochemical reactions, the cyclic voltammograms for oxidized carbons were recorded in blank aqueous electrolytes over a wide pH range. For CWN2—Ox and CWZ—Ox, aq.H2S04-aq. NaOH solutions of constant ionic strength were used [27]. The RKD—Ox carbon was studied in Britton-Robinson buffer. The CVs for different pH values recorded for CWZ—Ox carbon are shown in Fig. 17. In all the curves there are more or less well-defined cathodic and anodic peaks (or waves), the potentials of which are pH dependent. Some sections of the cathodic waves recorded in solutions of different pH are presented in Fig. 18. It can also be seen that the... 

The most reliable proof of the participation of several acids in an acid-base reaction is the increase of current %a with increasing buffer concentration at a given pH (fixed ratio of the acid and base eomponents of the buffer). Another proof can be given by comparison of wave recorded in buffers of the same pH but prepared from different acids and bases. 

Since the early beginning of the ECG, criteria have been sought that would allow for the diagnosis of MI. They consist in the presence of the necrosis Q wave or equivalents, especially the presence of RS morphology in VI as a mirror image of Q wave recorded in the back leads. The presence of Q wave or RS in VI as a mirror image is consequence of the changes in the first 40-50 milliseconds induced by necrosis (vector of infaction). 

Persistent (chronic) Q wave. Recording artefacts, normal variants (Figure 5.42) and different types of heart diseases (among them, hypertrophic cardiomyopathy (Figure 5.41) and congenital heart diseases) are included in this group. It is important to emphasise that often the duration of the Q wave is normal but its amplitude is... 

The pattern of negative T wave recorded in patients with IHD probably is not due to active ischaemia. 

FIGURE 3.14 Tafel plots for oxidation waves recorded in CVs at a V, ZrSi04-modified graphite electrode immersed into 2.50 mM cysteine plus 0.10 M NaOH. Potential scan rate, 20 mV/sec. 

To test these estimates of bottom disturbance by waves, a wave recorder was placed on Cable and Anchor Reef, where the water is 12.5 m deep, during the winter months of 1975. Water pressure was recorded continuously for 3 min each hour. Cable and Anchor Reef is surrounded by deep water and there is a long, open fetch to the east. The recorder is sensitive to pressure changes equivalent to 2 cm of water the period and amplitude of all recorded signals greater than this were read out and analyzed. The wavelength of the wave responsible for a pressure fluctuation 8p is found by graphical solution of the equation ... 

Fig. 3. Maximum horizontal water particle speed at the bottom on Cable and Anchor Reef, as calculated from wave-recorder records, and the square of the wind speed measured at Eatons Neck during a winter storm.

Figure 5.4.2 Shift of a reversible wave upon complexation of the reactant. Left curve is the reduction wave for Zn " in 1 M KCl at a Hg electrode E j2 — —1.00 V v. SCE). Right curve is for Zn in 1 M NH3 + 1 M NH4CI (F1/2 = -1.33 V V5. SCE). Complexation by ammonia lowers the free energy of the oxidized form, so that it is no longer possible to reduce Zn(II) to the amalgam at the potentials of the wave recorded in the absence of ammonia. By applying a more negative potential, the combined free energy of Zn(II) plus the 2e on the electrode is elevated to match that of Zn(Hg) and interconversion between Zn(II) and Zn(Hg) becomes possible.

The magnitude is given on the Richter scale, which was developed in 1935 by Charles F. Richter of the California Institute of Technology as a mathematical device to compare the size of earthquakes. The magnitude of an earthquake is measured by the logarithm of the amplitude of waves recorded by seismographs. Adjustments are included for the variation in the distance between the various seismographs and the epicenter of the earthquake. On... 

Blast wave recorded for a fireworks test salute, 50 g of flash powder [70 30, potassium perchlorate aluminum (German dark)]. 

Control cycle is one depolarization and repolarization of the transmembrane voltage. Control wave (or slow wave) is the continuing rhythmic electrical activity recorded at any one site. It was assumed to be generated by the smooth muscle cells behaving like a relaxation oscillator at that site. However, recent evidence [Hara et al, 1986 Suzuki et al. 1986 Barajas-Lopez et al, 1989 Serio et al, 1991] indicates that it is generated by a system of interstitial cells of Cajal (ICC) and smooth muscle cells at that site. ECA is the totality of the control waves recorded at one or several sites. Response Potentials (or spikes) are the rapid oscillations of transmembrane voltage in the depolarized state of smooth muscle cells. They are associated with muscular contraction and their occurrence is assumed to be in response to a control cycle when acetylcholine is present. ERA is the totality of the groups of response potentials at one or several sites. 

Experimental apparatus Electromagnetic emission source, electromagnetic energy meter (tesla), high frequency mechanical wave recorder, coal and rock strain recorder, methane, ethane, carbon monoxide sensors, data logger. 

The symmetrical appearance of the CV shown above is typical of a fully reversible redox process. The forward sweep (left to right on the CV above) records a maximum value of current (/p° ) associated with the oxidation process, while the reverse wave records a minimum value of current associated with reduction. The corresponding values of the potential are and (in V). The separation of these potentials, AE, is given by ... 

The wave measured automatically by the acoustic Doppler current Profiler ( AWAC wave Dragon) (Liu, J Lu, Z 2009). Measured data contains pressure, unit velocity along three oblique beams and wave height along a vertical beam (AST), the sampling frequency is 2 Hz, and each pulse emission sampling number is 2048, wave record every hour, each time record 18 minutes (no less than 100 waves). 

Maximum wave height In any wave record, there will also be a... 

Glaser SD, Weiss GG, Johnson LR (1998) Body waves recorded inside an elastic half-space by an embedded, wideband velocity sensor. L. Ac. Soc. Am. 104 (3),Pt. 1 1404-1412... 

Grover, F. H. 1974. Irfrasonic and Seismic Wave Records from the FUxborough and St. Bridget Explosions, AWRE Report 046/74. 

At the end of the waiting time the potential is stepped to values at which the product is oxidized B-> A + no,e. If the oxidation and the reduction are reversible processes (A = A and n d = Uo,), a single wave appears in the RPP mode (curve 1 in Fig. 27). It may be compared with the NPP wave recorded under the same conditions (curve 2 in Fig. 27). If the pulse potentials in RPP mode are still in the region of the DCP plateau, the current response, Irp (represented by the lower part of the curve 1) is identical with the limiting DCP current. If the pulse potentials in the RPP mode grow to sufficiently positive potentials so that the total oxidation of the product B proceeds, the limiting current I, Rp is obtained (see curve 1, the upper part). The relation between these... 

The significant wave height is the average height of the npper third of the wave heights in a wave record. 

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