Resistivity or specific resistance

Resistivity/Conductivity. The resistivity or specific resistance of a material is the electric resistance offered by an element of the material having unit length and unit cross-sectional area. The current iatensity is proportional to the voltage across its path, and is iaversely proportional to resistance. This relationship is expressed by Ohm s law, where I = current ia amperes, E = poteatial ia volts, and R = resistance ia ohms. 

Volume resistivity or specific resistance this is the resistance of a conductor of unit length and unit cross-sectional area. i.e. 

Volume resistivity Or specific resistivity of a material, expressed in W/cm. Resistance to electrical current flow through the bulk of an object. 

The resistivity (or specific resistance) of a conductor may be thought of as the resistance of a cube of 1-cm edge, with the current assumed to be uniform and perpendicular to two opposite faces of the cube. The resistance of a conductor of uniform cross section is given by... 

Mercury has a high density (13.546 g cm" at 20 °C) and a wide liquid range (mp -38.9 °C bp 357) over most of which its volume expands uniformly. In addition, the high surface tension of mercury keeps it from sticking to glass surfaces. These properties have contributed to its use in an impressive number of laboratory applications. For a metal, mercury has an unusually high electrical resistivity or specific resistance (95.8 J,S2 cm), and this property enables it to be used as an electrical standard. Of all the common metals, only bismuth has a higher resistivity. 

Resistivity or specific resistance (S) is defined as the electrical resistance (R) multiplied by the cross-sectional area of polymer test piece (A) and divided by its length (L) ... 

Comparative calculations of specific capacities of different filters or their specific filter areas should be made as part of the evaluation. Such calculations may be performed on the basis of experimental data obtained without using basic filtration equations. In designing a new filtration unit after equipment selection, calculations should be made to determine the specific capacity or specific filtration area. Basic filtration equations may be used for this purpose, with preliminary experimental constants evaluated. These constants contain information on the specific cake resistance and the resistance of the filter medium. 

High frequency of antibiotic resistance in the community or specific hospital unit... 

This term refers to how resistant the precision and accuracy of an assay is to small variations in the method, e.g. changes of instrumentation, slight variations in extraction procedures, sensitivity to minor impurities in reagents, etc. Robust assays may not be capable of the highest precision or specificity but they are regarded as fit for the purpose for which they are designed. 

To determine the group of compounds or specific compounds present in tissues of animals found positive by screening tests, a seven-plate test is often employed (108). This test is based on the susceptibility or resistance of four... 

Urease is remarkably resistant to unfolding in urea. No change in optical rotatory dispersion or specific activity of the enzyme occurs in concentrations of urea up to 8 M (7). Between 8 and 9M, unfolding occurs and the molecular weight becomes 60,000, but some activity persists. 

On the other hand, conductivity (cr) or specific conductance (reciprocal of resistivity p) is a material property that is normalized with respect to area, potential gradient, and time. It is expressed as the ratio of current density j (A cm-2) and electric field E (V cm-1). 

The conductivity or specific conductance is defined as the reciprocal of the specific resistance... 

Various phenolic compounds have been observed to Inhibit peroxidase-catalyzed lAA oxidation (1081 and -glucosldase (1091. However, no synthetic or specific Inhibitors for these enzymes are available that could be used to reduce weed resistance to plant pathogens. 

Some of these antitemplates have shown significant cytotoxicity in bacterial and mammalian cell culture assay systems126 . There is considerable evidence in the literature132 that bacterial and mammalian cells are capable of taking up intact DNA and RNA molecules. It has been suggested recently that one approach to cancer chemotherapy may be the uptake of normal RNA molecules or specifically defined oligonucleotides 133 . From the point of view of cellular uptake, the increased resistance which these antitemplates demonstrated toward the action of various nucleases appears to be particularly fortuitous. 

In Eqs. (3), (5), or (7), the permeability K or specific resistance or a are the key parameters to solve problem of flow through porous media. Many investigators have sought theoretical expressions from flow through incompressible beds by transforming parameters in pipe flow [Eqs. (1) and (2)] to flow through compactible porous media. 

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