Conductance Proportionality

The set-up of Fig. 11, 41, 3 ensures the complete condensation of the steam when a rapid flow of steam is necessary for satisfactory results, and is useful in the distillation of large volumes of liquids of low vapour pressure, such as nitrobenzene. Thus the flask A containing the mixture may be of 3-litre capacity and B may be a 1-litre flask the latter is cooled by a stream of water, which is collected in a funnel and conducted to the sink. The receiver C must be of proportionate size all stoppers... 

A general observation, verified for nearly all soHds, is a proportionality between current density and field strength, known as Ohm s law. The electrical conductivity is this proportionality constant and is defined as... 

Capillary Suction Processes. The force needed to remove water from capillaries increases proportionately with a decrease in capillary radius, exceeding 1400 kPa (200 psi) in a 1-p.m-diameter capillary. Some attempts have been made to use this force as a way to dewater sludges and cakes by providing smaller dry capillaries to suck up the water (27). Sectors of a vacuum filter have been made of microporous ceramic, which conducts the moisture from the cake into the sector and removes the water on the inside by vacuum. Pore size is sufficiently small that the difference in pressure during vacuum is insufficient to displace water from the sector material, thus allowing a smaller vacuum pump to be effective (126). 

The parameter, K, is a proportionality constant that is known as the hydraulic conductivity. 

The rate of flow of heat is proportional to the difference in temperature through the solid and the heat transfer area of the solid, and uiverse) proportional to the thickness of the solid. The proportionality coiislain. f. is known as the thermal conductivity of the solid. Thus, the rjiiaiility o heat l lo may he CNpressed by the following equation ... 

The electrical conductivity is proportional to n. Equation 1.168 therefore predicts an electrical conductivity varying as p. Experimental results show proportionality to p and this discrepancy is probably due to incomplete disorder of cation vacancies and positive holes. An effect of this sort (deviation from ideal thermodynamic behaviour) is not allowed for in the simple mass action formula of equation 1.167. 

A conductive polymer electrode has been designed specifically for the cathodic protection of steel reinforcing bars in concrete and is marketed under the trade name Ferex . The anode consists of a 16 AWG stranded copper conductor surrounded by a carbon-loaded polymeric coating similar to that used on the Anodeflex system ) to provide a nominal anode diameter of 8 mm The manufacturer claims that at the maximum recommended current density of 0 08 Am the anode life in concrete will be 32 years with a proportionately longer life at lower current densities. 

The proportionality constant between the current and the electrochemical potential gradient is controlled by the partial electrical conductivity [Pg.546]

The theoretically derived formula (21) relating PMC measurements to the surface concentration of minority carriers and interfacial rate constants contains a proportionality constant, S, the sensitivity factor. This factor depends on both the conductivity distribution in the semiconductor elec-... 

Although the transport properties, conductivity, and viscosity can be obtained quantitatively from fluctuations in a system at equilibrium in the absence of any driving forces, it is most common to determine the values from experiments in which a flux is induced by an external stress. In the case of viscous flow, the shear viscosity r is the proportionality constant connecting the magnitude of shear stress S to the flux of matter relative to a stationary surface. If the flux is measured as a velocity gradient, then... 

In conductive heat transfer, the transfer is always in the direction of decreasing temperature and is proportional to the magnitude of the temperature gradient the constant of proportionality being the thermal conductivity of the system. 

Expressions (1.45) and (1.46) which are valid in case of applicability of above assumptions indicate on availability of direct proportionality between the value of the change of the surface-adjacent conductivity of semiconductor adsorbent and concentration of chemisorbed particles on its surface, the latter being in charged form. This results in the fact that when the surface is covered by adsorbed particles at degrees lower... 

We should point out that the initial rate of the change in electric conductivity during adsorption of radicals follows above proportionality as well. Using the expression (2.94) we also obtain... 

This variation of electric conductivity is caused by the reaction ->, where a is the coefficient of proportionality, 0 is the... 

The constant of proportionality k is known as the thermal conductivity of the material and the above relationship is known as Fourier s law for conduction in one dimension. The thermal conductivity k is the heat flux which results from unit temperature gradient in unit distance. In s.i. units the thermal conductivity, k, is expressed in Wm"1 K. Integration of Fourier s law yields... 

Because of the interionic forces, the conductivity is directly proportional to the concentration only at low concentrations. At higher concentrations, the conductivity is lower than expected from direct proportionality. This decelerated growth of the conductivity corresponds to a decrease of the molar conductivity. Figure 2.4 gives some examples of the dependence of... 

Using Eq. (2.6.18) the temperature dependence of various transport properties of polymers, such as diffusion coefficient D, ionic conductivity a and fluidity (reciprocal viscosity) 1/rj are described, since all these quantities are proportional to p. Except for fluidity, the proportionality constant (pre-exponential factor) also depends, however, on temperature,... 

Fick first recognized the analogy among diffusion, heat conduction, and electrical conduction and described diffusion on a quantitative basis by adopting the mathematical equations of Fourier s law for heat conduction or Ohm s law for electrical conduction [1], Fick s first law relates flux of a solute to its concentration gradient, employing a constant of proportionality called a diffusion coefficient or diffu-sivity ... 

ES is normally operated at low total electrolyte concentrations, C < 10-2 mol/L. For such concentrations a simple proportionality between the conductivity K and the concentration C holds ... 

Constant conduction heat pipes, 13 227 Constant failure rate, 13 167 Constant-field scaling, of FETs, 22 253, 254 Constant-modulus alloys, 17 101 Constant of proportionality, 14 237 Constant pressure heat capacity, 24 656 Constant rate drying, 9 103-105 Constant rate period, 9 97 23 66-67 Constant retard ratio (CRR) mode, 24 103 Constant slope condition, 24 136-137 Constant stress test, 13 472 19 583 Constant-voltage scaling, of FETs, 22 253 Constant volume heat capacity, 24 656 Constant volume sampling system (CVS), 10 33... 

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