Functional electrical resistance

In Equation 4.7, the functional electrical resistance (ERf) is calculated from the measured electrical resistance (ERm) divided by the fraction of remaining area open for ionic flow. The area open for ionic flow is calculated by subtracting the fraction of area occupied by gas (GA) from the whole. 

Further improvements in lowering separator electrical resistance have come with the use of wetting agents to ensure complete wetting of the pores, and modifications to the silica concentration or silica type in the separator [41]. Besides lowering the measured separator resistance, a proposal has been made to also lower the functional electrical resistance. The functional resistance of the separator is the measured resistance compensated for area occupied by gas bubbles. Therefore, any work to lower the entrapped gas of the separator will also serve to improve the measured power output of a battery [8]. 

Evidence for the existence of significant amounts of N has been found from interpretation of reaction orders [607,614,617,652-654], from a comparison of work function, electrical resistance and catalyst activity [655], from laser fluorescence [656], from the observation of N by electron spectroscopy on the catalyst [52] or a Fe single crystal [414, 603, 604] after exposure to NH3 synthesis conditions, and from thermodynamic estimates based on data measured for the intermediates on single crystal surfaces [550]. 

As indicated in Figure 4, the basic thermoelectric parameters are all functions of carrier concentration. Thus adjusting the dopant level to increase the output voltage generally also increases the electrical resistance. In addition, it affects the electronic component of the thermal conductivity. However, there are limitations on what can be accompHshed by simply varying the carrier concentration in any given material. 

Uses. In spite of unique properties, there are few commercial appUcations for monolithic shapes of borides. They are used for resistance-heated boats (with boron nitride), for aluminum evaporation, and for sliding electrical contacts. There are a number of potential uses ia the control and handling of molten metals and slags where corrosion and erosion resistance are important. Titanium diboride and zirconium diboride are potential cathodes for the aluminum Hall cells (see Aluminum and aluminum alloys). Lanthanum hexaboride and cerium hexaboride are particularly useful as cathodes ia electronic devices because of their high thermal emissivities, low work functions, and resistance to poisoning. 

C), (cmVohm geqmv) K = Ci/R = specific conductance, (ohm cm) h C = solution concentration, (gequiv/ ) Ot = conductance cell constant (measured), (cm ) R = solution electrical resistance, which is measured (ohm) and/(C) = a complicated function of concentration. The resulting equation of the electrolyte diffusivity is... 

Fig. 5. Electrical resistance as a function of the temperature at the indicated magnetic fields for a single microbundle of carbon nanotubes. The solid line is a fit using the two-band model for graphite (see inset) with an overlap A = 3.7 meV and a Fermi level right in the middle of the overlap (after Langer et at. l9 ).

The low electrical conductivity of PET fibers depends essentially on their chemical constituency, but also to the same extent on the fiber s fine structure. In one study [58], an attempt was made to elucidate the influence of some basic fine structure parameters on the electrical resistivity of PET fibers. The influence of crystallinity (jc) the average lateral crystallite size (A), the mean long period (L), and the overall orientation function (fo) have been considered. The results obtained are presented in the form of plots in Figs. 9-12. 

It should be noted that studying states of order in thermal equilibrium as a function of temperature yields the possibility of measuring the degree of order of a system in values of corresponding equilibrium temperature . This way, the results of residual resistometry are independent of the detailed formalism between state of order and electrical resistivity... 

The low conductivity of high-purity water makes it difficult to study electrode processes potentiostatically, since too high an electrical resistance in the circuit can affect the proper functioning of a potentiostat, and it can also introduce large iR errors. The increase in conductivity of water with temperature has been measured and /7 -corrected polarisation data have been obtained in hot water that originally had very low conductivity at room temperature. Other results in high-temperature water are all for tests where the conductivity was deliberately increased through the addition of electrolytes. 

Figure 5. Cold crank voltage as a function of separator electrical resistance )...

If a heated wire is immersed in a fluid, the rate of loss of heat will be a function of the flowrate. In the hot-wire anemometer a fine wire whose electrical resistance has a high temperature coefficient is heated electrically. Under equilibrium conditions the rate of loss of heat is then proportional to /2f2, where Q. is the resistance of the wire and / is the current flowing. 

The proportionality factor p (units Q. cm ) formally has the same function as the electric resistance (per unit cross-sectional area) in Ohm s law, hence is sometimes called the reaction resistance. However, this resistance is not ohmic. 

Dilute gold alloys with Cu, Ag, Ni, Pd, and Pt as absorbers Correlation of isomer shift with residual electrical resistivity, wave function at Fermi level, s--band population of gold... 

Au-Cu and Au-Ag alloys Isomer shift and electrical resistivity as function of alloy composition and, in CU3AU, of pressure model to describe 5 in terms of average atomic volume, of short-range parameter and alloy composition average charge density on Au... 

As discussed in Chapter 10, a wide variety of additives is used in the polymer industry. Stabilizers, waxes, and processing aids reduce degradation of the polymer during processing and use. Dyes and pigments provide the many hues that we observe in synthetic fabrics and molded articles, such as household containers and toys. Functional additives, such as glass fibers, carbon black, and metakaolins can improve dimensional stability, modulus, conductivity, or electrical resistivity of the polymer. Fillers can reduce the cost of the final part by replacing expensive resins with inexpensive materials such as wood flour and calcium carbonate. The additives chosen will depend on the properties desired. 

Fig. 2. Typical curves of the relative changes of the electrical resistance of nickel films as a function of time (a) adsorption of one dose of hydrogen on the surface, partially covered by preadsorbed oxygen (b) adsorption of one dose of oxygen on the surface, covered by preadsorbed hydrogen (both at 300°K).

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