External circuit loop

It is easy to control rate and reaction conditions by using external circuit loop (e.g. constant voltage) to control overvoltage, so that vigorous electrolysis and redox reaction are realized. 

In conventional systems, a closed current22 loop contains the generator or battery source dipole as well as the external circuit s loads and losses. This... 

More rigorously, this is any closed current loop circuit where the charge carriers in all portions of the loop have the same m/q ratio. For example, battery-powered circuits do not meet that condition, since the internal ionic currents between the battery plates may have m/q ratios several hundred times the m/q ratio of the electrons that pass between the outsides of the two plates and through the external circuit containing the load. With Bedini s process, a battery-powered system can be made to charge its batteries at the same time that it powers its load see Bearden [17]. 

First, we note that the standard photodetection is a local measurement of the field variables (intensities). At the same time, the Aharonov-Bohm effect represents a topological measurement referred to the properties of vector potential along some loop. In the usual form, the Aharonov-Bohm effect deals with static or slowly time-varying magnetic fields [101]. The effect consists in the appearance of a persistent current in a metallic loop over which the magnetic flux passes. This current is a periodic function of magnetic flux with the period of flux quantum hc/e. Besides that, certain resistance oscillations in the loop incorporated into an external circuit with the same period can occur. 

Two important cases of negative differential conductivity (NDC) are described by an iV-shaped or an -shaped j (F) characteristic, and denoted by NNDC and SNDC, respectively. However, more complicated forms like Z-shaped, loop-shaped, or disconnected characteristics are also possible [15]. NNDC and SNDC are associated with voltage- or current-controlled instabilities, respectively. In the NNDC case the current density is a singlevalued function of the field, but the field is multivalued the F j) relation has three branches in a certain range of j. The SNDC case is complementary in the sense that F and j are interchanged. In case of NNDC, the NDC branch is often but not always - depending upon external circuit and boundary conditions - unstable against the formation of nonuniform field... 

PHENTX, SUPERPHENIX and PFR are so-called pool reactors, whereas the other three projects are loop reactors. In a pool reactor, the whole primary heat transfer system including main pumps and intermediate heat exchangers is integrated into the reactor vessel (pool), while the loop reactors have parallel primary sodium heat transfer circuits (loops) with the main heat transfer components external to the reactor vessel. The secondary heat transfer system, installed between primary system and water/steam system for safety reasons, is practically identical in both cases. It also consists of three parallel circuits. Live steam conditions and the achievable efficiency are very similar in all plants 500°C, 165 bar, 40%. These are close to the conditions of coal-fired stations. 

Figure 3.13. Diagram of the electrical circuit for a controUed-potential electrochemistry-ES emitter. Floated potentiostat common is that of the ES high-voltage supply. W, R, and A represent the working, reference, and auxiUary electrodes in the electrochemical ceU, respectively, /w, Aux, fe, ext are the currents in the working electrode, auxiUary electrode, ES spray current, and upstream external current loop, respectively. In standby mode the electrodes remain connected to the ES high voltage, but the worki ng electrode potential is not controlled with the potentiostat. (Adapted with permission from Ref. 89. Copyright 2005, American Chemical Society.)...

Instruments with a balanced input circuit are available for measurements where both input terminals are normally at a potential other than earth. Further problems arise due to common-mode interference arising from the presence of multiple earth loops in the circuits. In these cases the instrument may need to be isolated from the mains earth. Finally, high-frequency instruments, unless properly screened, may be subject to radiated electromagnetic interference arising from strong external fields. 

If the circuit is made up of two or more loops, the total external work done is the algebraic sum of the areas of the loops. 

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