Rectifying effect

The group in the Swiss Federal Institute of Technology [55] has fabricated a macroscale device by depositing the conducting polymer (poly(/j-phenylenevinylene)) on the MWCNT film (Fig. 16). They have observed the characteristic rectifying effect from the l-V curve, which suggests the CNTs inject holes efficiently into the polymer layer. However, due to the difficulty in... 

Pick-up of stray current (a.c. or d.c.) (Section 10.5). Decreased use of d.c. in many areas has led to less possibilities of pick-up of direct current from utilities, mines, etc. The importance of grounded a.c. systems has been discounted, but Waters has shown that alternating currents can accelerate corrosion. Furthermore the rectifying effects of oxide films, clay minerals and other soil factors are not understood. 

In fact, in order to optimize the rectifying effect, one should avoid the overlapping of the phonon bands in the low temperature limit (Eq.6) and that in the high temperature limit (Eq.7) for each segment of the system. According to the above estimates, one should have V > 4k, which is satisfied for the case of Fig.8. 

We should stress that it is the nonlinearity of the potential that makes phonon spectra temperature dependent, and thus the rectifying effect possible. Therefore it is reasonable to expect the rectifying effect to be present, in different degrees, in typical nonlinear lattices. 

Finally we have shown the possibility to build a thermal diode which exhibits a very significant rectifying effect in a very wide range of system parameters. Moreover, based on the phenomenon of negative differential thermal resistance observed in the thermal diode, we have built a theoretical model for a thermal transistor. The model displays two basic functions of a transistor switch and modulator/amplifier. Although at present it is just a model we believe that, sooner or later, it can be realized in a nanoscale system experiment. After all the Frenkel-Kontorova model used in our simulation is a very popular model in condensed matter physics(Braun and Kivshar, 1998). 

Fig. 10. Rectifier effect in the system Ag/phthalocyanine mixed crystal/Al (after Ref. 124>)...

Tetraphenylporphine (TPP) and other metal porphyrine derivatives coated on platinum (87,88,89) or gold (89,90) electrodes have been investigated in photoelectrochemical modes. Photocurrents reported are cathodic or anodic, depending on the pH as well as the composition of the electrolyte employed. Photocurrent quantum efficiencies of 2% (89) to 7% (87) were reported in systems using water itself or methylviologen as the redox species in aqueous electrolyte. Photocurrent generation at Zn-TPP-coated metal cathodes (89) was interpreted in terms of a rectifying effect of the Schottky barrier formed at a metal-p-type... 

Besides the transference numbers Schlogl and Schodel were able to calculate the concentration profiles in the membrane. If the solution concentrations are different on both sides of the membrane, these profiles change if the direction of the current is reversed. By consequence, the electrical resistance depends on the direction of the current. This is called the rectifier effect. 

The calculated source of 2.2 ( 0.8) PgC yr for the 1990s (Houghton, 2003) is very different from the global net terrestrial sink determined from top-down analyses (0.7 PgC yr ) (Table 8). Are the methods biased Biases in the inverse calculations may be in either direction. Because of the rectifier effect (the seasonal covariance... 

Valve metals bear this name due to the fact that they pass current in only one direction (rectifying effect), that is, the anodic current is low for potentials lower than the... 

A composite membrane prepared, e.g., by lamination of a cation exchange membrane with an anion exchange membrane, called a bipolar ion exchange membrane, shows interesting properties, for example water splitting to generate hydrogen ions and hydroxide ions at the interface of both membranes in electrodialysis, or a rectifier effect.110 When the current is passed from one direction. 

Otherwise, all the current lines would have had to cross this zone and the effect of the three boundary point would have been confused with the rectifier effect generally attributed to the junction oxide/electrodes. 

High-frequency current used in electrosurgery does not result in living tissue excitation. However, electric arcs imply a local rectifying effect generating nerve and muscle excitation in the very vicinity of an arc. In the active electrode wire, a blocking safety capacitor is inserted so the rectified voltage shall result in only small AC low-frequency... 

Fan J, Wan M, Zhu D (1998) Studies on the rectifying effect of the heterojunction between porous silicon and water-soluble copolymer of polyanhine. Synth Metals 95 119-124 Gallach D, Torres-Costa V, Garcia-Pelayo L et al (2012) Properties of bilayer contacts to porous silicon. Appl Phys A 107 293-300... 

Monocrystals exhibit n- and p-type conductivity with thermoelectric powers a= -317 and +217 iV/K, respectively. The electrical resistivity is -10" Q-cm. The crystals show a rectifying effect, Yarembash etal. [7]. 

A compilation of publications concerning conductivity, photoconductivity, thermopower. Hall-effect and rectifying effects in polyacetylene is shown in Fig. 17j but by no means this list can claim completeness. 

ChannelType K+ channels Outward rectifier Effect Concentration m... 

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