Pulse ultrasonic relaxation method

Pulse ultrasonic relaxation method, 32 18 Pump-and-probe techniques, 46 137 Purification, of actinide metals, see Actinide, metals, purification XjPj Purified protein, 36 94 Purple acid phosphatases, 40 371, 376, 43 362, 395-398, 44 243-245 biological function, 43 395 homology, 43 397... 

Apart from the temperature-jump technique, other relaxation methods that have been used are those of ultrasonic absorption" " and electric-field pulse. Another technique that has been used for some of the more slowly included guest molecules is that of stopped-flow. ... 

Relaxation methods can be classified as either transient or stationary (Bernasconi, 1986). The former include pressure and temperature jump (p-jump and t-jump, respectively), and electric field pulse. With these methods, the equilibrium is perturbed and the relaxation time is monitored using some physical measurement such as conductivity. Examples of stationary relaxation methods are ultrasonic and certain electric field methods. Here, the reaction system is perturbed using a sound wave, which creates temperature and pressure changes or an oscillating electric field. Chemical relaxation can then be determined by analyzing absorbed energy (acous-... 

Chemical relaxation methods are widely used to study the kinetics of fast chemical reactions in solution. In particular, ultrasonic absorption techniques have been used to investigate fast exchange processes with relaxation times in the range 0.3 xs to 0.3 ns. The longer end of this time range has become accessible in recent years through the use of cylindrical resonator methods [1] which have lowered the frequency range covered by fictional pulse echo methods. 

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