Transport currents

The simplest and most widely used model to explain the response of organic photovoltaic devices under illumination is a metal-insulaior-metal (MIM) tunnel diode [55] with asymmetrical work-function metal electrodes (see Fig. 15-10). In forward bias, holes from the high work-function metal and electrons from the low work-function metal are injected into the organic semiconductor thin film. Because of the asymmetry of the work-functions for the two different metals, forward bias currents are orders of magnitude larger than reverse bias currents at low voltages. The expansion of the current transport model described above to a carrier generation term was not taken into account until now. 

The fraction of current transported by ions of a given type is called the transport... 

In the example just studied, the electrolysis of HC1 solution, the ions that transport the current (H+ and Cl-) are also the ones that are discharged at the electrodes. In other cases, however, the main ionic transporters of current may not be of the same species as the ions that are discharged. An excellent example is the electrolysis of CuS04 solution between platinum electrodes. A one molal CuS04 solution is quite acid so that the positive current transporters are both Cu2+ and H+ ions. The main negative transporter is the S04 ions. The solution contains, however, a small concentration of OH- ions. In order to determine which ions will be discharged at the electrodes, it is necessary to consider standard electrode potentials of the concerned species ... 

Conduction of electric current—transport of charge and mass as the result of the motion of elecrically charged particles in an electric field. 

Thieblemont F, Seitz O, Vilan A, Cohen FI, Salomon E, Kahn A, Cahen D (2008) Electronic current transport through molecular monolayers comparison between Hg/alkoxy and alkyl monolayer/Si(100) junctions. Adv Mater 20 3931-3936... 

By combining the findings of Cacchione, Drake and the results reported here, a coherent model can be proposed to explain the deposition inventory of the radionuclides. The down-canyon current transports large quantities of sediment toward the radioactive waste disposal site at 4000 m. Within the upper canyon, fine material is transported the furthest. Near the mouth of the canyon, sediment erosion of the walls occurs due to the down-canyon currents meeting a proposed opposing on-shore bottom current. The eroded material from the walls is transported and the finer material is deposited in eddies formed where the two currents meet. 

PE Burrows, Z Shen, V Bulovic, DM McCarty, SR Forrest, JA Cronin, and ME Thompson, Relation between electroluminescence and current transport in organic heterojunction light-emitting devices, J. Appl. Phys., 79 7991-8006, 1996. 

If the water currents transport the pollutant cloud directly to the intake of the water plant, the transport time would be about ... 

The electrode reactions are comprised of the oxidation of hydrogen on Ihe anode (the negative electrode) to hydrated protons with the release ol electrons and on the cathode (the positive electrode) the reaction of oxygen with protons la I unn water vapor with the consumption of electrons. Electrons llow from the anode through the external load to the cathode and the circuit is closed by ionic current transport through the electrolyte. In an acid cell, the current is carried by protons. 

The goal of the present study was to identify regions of negligible transport control for future mechanistic studies. In the following, a systematic approach to the current transport/reaction problem is presented. 

At 0.05 N the current transported by Cl- ions was determined separately. The specific conductivity of the Na+ ions in the membrane was determined from the conductivity of the membrane, taking into account the current transport of the Cl" ions. 

Separations are now effected, because the concentrations of the various co-ions in the membrane are generally different e.g. for a univalent co-ion this concentration is higher than for a bivalent co-ion. The current efficiency is low due to the large contribution of H+ and OH- ions to the current transport, especially at higher current densities. 

Gas produced by the Early Oil Production (EOP) project is currently transported via Oil Rocks and the Bahar gas field to the Gas Processing Plant at Karadagh. Constraints on the 400 mm pipeline limit the flow of gas to 2.8 Mcm/d, such that approximately 750,000 m3/day is flared. This will continue until the start of gas deliveries from the ACG Phase 1 development, planned for 2005. 

For the Daniell cell, given by reaction (VI), what are the electrode reactions Sketch the cell. How is current transported within the cell Assuming that the smaller Zn2+ ions tend to diffuse faster, what is the direction of the junction potential ... 

Here Xj and x2 stand for the respective specific conductivity of chloride and hydroxide of an alkali metal, x stands for the part of current transported toward the anode by caustic and (1 — x) for the part of current transported by the chloride ions toward the Bame electrode. 

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