Composition actor

Polarization cell Measurement of kinetic data by polarization Electrochemical composition actors (electrolyzers, pumps, windows), electrochemical composition sensors (amperometric, conductometric)... 

There is an extended special literature3,10-16 on applications of solid state electrochemistry and even more on electrochemical devices. According to our objective, in this section applications will be emphasized in which migration and diffusion in the solid state are decisive processes (as discussed in Part I2). We intend to subsume such applications under the headlines composition sensors, composition actors, and energy storage or conversion devices. 

We will begin with a description of electrochemical sensors or more specifically composition sensors based on electrochemical principles (i.e., we refer to an electrochemical detection of composition). Another group of applications refers to devices in which the transference of mass and charge is used primarily to change composition or produce chemicals (electrochemical pumps and electrochemical reactors, or electrochemical filters) we will term such devices composition actors. At the end we will discuss energy conversion and storage devices (which we do not subsume under the term composition actors as here the energy aspect is to the fore). 

In this section we will describe what may be called electrochemical composition actors, in which chemical action—and not mechanical action as usually described by the term actor (or actuator)—is caused by electrical excitation. Unlike electrochemical composition sensors which detect chemical composition via electrochemical methods, they cause changes in chemical composition. It shall not remain unmentioned that at present interesting work is pursued also to realize mechanical action on an electrochemical stimulus ( artifical muscles ).48... 

We have now illustrated, in a few typical examples, some of the actors that go into the planning and execution of a contemporary organic synthesis. One could well ask at this point, Is it possible to formulate a set of general rules that may direct the composition of an optimal synthetic plan Let us state up front that no such summary of rigorous rules exists that define a sequence of steps to be taken in the solution of some given synthetic task. It is possible, however, to list several general recommendations which, while not universal, are unquestionably useful in the planning a synthesis. 

The ai subunits of the CUyl and Cay2 channels associate with ancillary p subunit (encoded by four different genes), a2/5 subunits (four genes known), and possibly y subunits (ten genes known). Although tti subunit has been considered as the central actor in these Ca channel complexes, auxiliary subunits aid membrane expression and alter the biophysical properties of the tti subunit [102,109,118,119], In contrast, the subunit composition of the Cay3 channels remains an open controversial issue [120],... 

With this in mind, we arrive at the transitory character of the Methode s classification. This classification portrays the state of art in the chemistry of pure chemical substances at a certain point in time, and each change in this state must have repercussions for it. Its expiry date depended on the pace of further developments in this domain of chemical investigations. This was as obvious to the historical actors as it is to us. But presumably nobody expected back in 1787 that major revisions would prove necessary only two years later. In his Trade of 1789, Lavoisier proposed classificatory distinctions and distributions of pure chemical substances that amounted to a dismissal of the Methode s compromise between the two conflicting classificatory principles, classification according to composition and the construction and arrangement of classes in conformity with the conception of neutral salts. For a demonstration of the transitory character of the Methode s classification, it is not necessary to scrutinize Lavoisier s classificatory attempt. It suffices to mention here that this attempt actually manifests what was said about the latent tensions between the classificatory stmcture derived from the conception of neutral salts and the principle of classification according to composition. 

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