Electrical conductivity definition

Surface conductance Surface electric conductance Definition... 

Starting with this definition the semiconductor diemical sensors can be arbitrary classified with respect to following features the type of electrophysical characteristics diosen for monitoring, such as electric conductivity, thermal-electromotive force, work function of electron, etc. type and nature of semiconductor adsorbent used as an operational element of the sensor and, finally, the detection method used for monitoring the adsorption response of electrophysical characteristics of die sensor. 

It is well known that the flow of either the positive or the negative ions, or of both, is responsible for the electric conduction process through the body of the solution of an electrolyte. Let the fraction of the current carried by each ion in a given electrolyte be considered. For this purpose, the transference numbers mentioned in the previous section are introduced according to the definitions... 

A classic definition of electrochemical ultracapacitors or supercapacitors summarizes them as devices, which store electrical energy via charge in the electrical double layer, mainly by electrostatic forces, without phase transformation in the electrode materials. Most commercially available capacitors consist of two high surface area carbon electrodes with graphitic or soot-like material as electrical conductivity enhancement additives. Chapter 1 of this volume contains seven papers with overview presentations, and development reports, as related to new carbon materials for this emerging segment of the energy market. 

In an individual molten carbamide, the electrode processes are feebly marked at melt decomposition potentials because of its low electrical conductivity. Both electrode processes are accompanied by gas evolution (NH3, CO, C02, N2) and NH2CN (approximately) is formed in melt. In eutectic carbamide-chloride melts electrode processes take place mainly independently of each other. The chlorine must evolve at the anode during the electrolysis of carbamide - alkali metal and ammonium chloride melts, which were revealed in the electrolysis of the carbamide-KCl melt. But in the case of simultaneous oxidation of carbamide and NH4CI, however, a new compound containing N-Cl bond has been found in anode gases instead of chlorine. It is difficult to fully identify this compound by the experimental methods employed in the present work, but it can be definitely stated that... 

The fundamental division of materials when electrical properties are considered is into metals, insulators, and semiconductors. An insulator is a material that normally shows no electrical conductivity. Metals and semiconductors were originally classified more or less in terms of the magnitude of the measured electrical conductivity. However, a better definition is to include in metals those materials for which the... 

An important point is that the electrochemically driven charge transport in these polymeric materials is not dependent on the presence of mixed valence interactions which are well known to give rise to electronic conductivity — in a number of cation radical crystalline salts. This is clearly seen from the absorption spectrum of the electrochemically oxidized pyrazoline films (Figure 8) which show no evidence for the mixed valence states that are the structural electronic prerequisites for electrical conductivity in the crystalline salts. A more definitive confirmation of this point is provided by the absorption spectrum (Figure 10) of electrochemically oxidized TTF polymer films which shows... 

Look up the definitions of the terms luster, malleability, and electrical conductivity. To what elements do they apply ... 

Instead of adhering to the sequence of the periodic table, the pure oxide melts discussed in this section are being broadly divided into three main liquid types. These are the network liquids, the electrically conducting melts and the molecular liquids. It is emphasized that this distinction is not definitive in every case and serves only to illustrate the wide range of liquid properties and structures encountered. 

Measurements of the electrical conductivity of solutions of alkali tantalates have been made,1 but no definite conclusions are deducible as to the complexity of the ions present. 

The electrical conductivity of a pure arsenic crystal has been measured 3 at temperatures down to 2-42° Abs. The resistance-temperature curve is similar to those of pure metals. There is evidence of definite residual resistance being maintained at low temperatures, but arsenic does not exhibit the abnormally high residual resistance shown by bismuth, nor does it show superconductivity. The resistance is by no means proportional to the absolute temperature. It has been estimated that the electrical resistance of liquid arsenic at the melting point is about 0-4 of that of the solid phase.4... 

With the introduction of the lattice structure and electroneutrality condition, one has to define two elementary SE units which do not refer to chemical species. These elementary units are l) the empty lattice site (vacancy) and 2) the elementary electrical charge. Both are definite (statistical) entities of their own in the lattice reference system and have to be taken into account in constructing the partition function of the crystal. Structure elements do not exist outside the crystal and thus do not have real chemical potentials. For example, vacancies do not possess a vapor pressure. Nevertheless, vacancies and other SE s of a crystal can, in principle, be seen , for example, as color centers through spectroscopic observations or otherwise. The electrical charges can be detected by electrical conductivity. 

Definitions and Units. Electrolytic conductivity is often defined as the electrical conductance of a unit cube of solution as measured between opposite faces. It is expressed in the same units as electrical conductivity, i.e.. reciprocal ohms per unit length. Most commonly wc find Mho/eemimeter (fU cm"1). siemens/cenlimeter IS cm 1), and siemcns/meler (S cnT1) ... 

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