Electrical conductivity experimental data

Danek and his group have independently proposed a quite similar model, which they call the dissociation modeV - For this model Olteanu and Pavel have presented a versatile numerical method and its computing program. However, they calculated only the electrical conductivity or the molar conductivity of the mixtures, and the deviation of the internal mobilities of the constituting cations from the experimental data is consequently vague. 

Figure 11. Experimental and predicted differential conductance plots of the double-island device of Figure 10(b). (a) Differential conductance measured at 4.2 K four peaks are found per gate period. Above the threshold for the Coulomb blockade, the current can be described as linear with small oscillations superposed, which give the peaks in dljdVj s- The linear component corresponds to a resistance of 20 GQ. (b) Electrical modeling of the device. The silicon substrate acts as a common gate electrode for both islands, (c) Monte Carlo simulation of a stability plot for the double-island device at 4.2 K with capacitance values obtained from finite-element modeling Cq = 0.84aF (island-gate capacitance). Cm = 3.7aF (inter-island capacitance). Cl = 4.9 aF (lead-island capacitance) the left, middle and right tunnel junction resistances were, respectively, set to 0.1, 10 and 10 GQ to reproduce the experimental data. (Reprinted with permission from Ref [28], 2006, American Institute of Physics.)...

The comparison of experimental data on adsorption of various particles on different adsorbents indicate that absorbate reaction capacity plays a substantial role in effects of influence of adsorption on electric conductivity of oxide semiconductors. For instance, the activation energy of adsorption of molecular oxygen on ZnO is about 8 kcal/mole [83] and molecular hydrogen - 30 kcal/mole [185]. Due to such high activation energy of adsorption of molecular hydrogen at temperatures of adsorbent lower than 100 C (in contrast to O2) practically does not influence the electric conductivity of oxides. The molecular nitrogen and... 

Nevertheless, there is a whole series of experimental results enabling one to propose and substantiate a sufficiently general model consistently describing the effect of oxygen adsorption on electric conductivity of partially reduced oxides observed in experiments. Let us con sider these data. 

The fair agreement of expressions (2.67) and (2.71) with experimental data as well as agreement of independently obtained experimental data concerning kinetics of the change of a with the data on equilibrium enabled the author of paper [89] to conclude that the proposed mechanism of effect of hydrogen on electric conductivity of semiconductors can be one of active mechanisms. The heat of total reaction (2.63) calculated from the values found was about 4.6 kcal. 

As it has been shown in Section 1.11 a comparison of experimental data on effects of adsorption of various particles on electric conductivity of oxide adsorbents results in conclusion that the dominant role in this... 

Figure 4.23 shows the results of measuring the electric conductivity of the semiconductor sensor obtained by remote control means from board of the rocket MR-12, along with the data obtained in our experiments and the data of model calculations by other authors. Also shown are the experimental results of similar measurements obtained by other... 

Figure 39. Comparison of theoretical j- U curves with experimental data on electrical conduction of aluminum (curve I) and tantalum (curve II) oxides.62...

Some of the properties that are being used to follow the course of reaction are indicated by the data of the problems in Section P3.4. Such a property should depend strongly and uniquely on the quantity of a key participant. Reports of the experimental work usually need not provide the instrument reading, I, but only the calibrated value of the concentration or amount of the key. When the calibration is linear, such as a polarimeter reading or electrical conductivity, it may be convenient to develop a rate equation of the form... 

Figure 9.15 shows how the electric conductivity of SWCNT-filled composites increases with SWCNT concentration (Park et al., 2002). The solid curve is the fit to the experimental data using the classical percolation power law. a = o0(K- F) ... 

Data for the electrical conductance of annealed samples shows that ionic transport is more restricted in comparison with those which are nonannealed [Table IV). Since the total number of ion-exchange sites is unaffected by the annealing process (cf. experimental) we may assume that the site to site distance has increased. 

The change in the work function and the electrical conductivity of the semiconductor due to chemisorption is the second important consequence of the theory. These effects have been theoretically considered in detail by Sandomirsky 46-48) They have been observed experimentally by a number of authors 49-64)- Some of the experimental data are presented in Table I, where the signs -f- and — denote, respectively, positive and negative surface charging upon chemisorption (Ao- > 0 or Ac < 0) these data have been obtained from the variation of the work function or of the electrical conductivity or both simultaneously. The symbol x in the table denotes that the surface charge is not affected by chemisorption (Ao- = 0) the figures in brackets refer to the literature. 

If the conductivity type and the character of the relation between the electrical conductivity and the catalytic activity for the given reaction are known and the validity of Equation (23) is assumed, one may conclude from the experimental data to what type (n or p) the given reaction belongs. This may be useful in a theoretical analysis of the reaction mechanism. 

Plambeck [16] summarizes the important physical properties of the molten LiCl-KCl eutectic such as density, viscosity, and electrical conductivity and gives references to some other sources of this data. Tabulated physical property data for FLINAK are scarce but are available in experimental articles. 

In concluding this section on liquid-liquid phase transitions, we briefly consider the available experimental information on the ion distribution near criticality. In the absence of scattering experiments, most experimental data come from electrical conductance data [72, 137, 138]. Moreover, there are some data on the concentration dependence of the dielectric constant in low-s solutions [139] and near criticality [138]. 

Diffusion-Controlled Reactions. The specific rates of many of the reactions of elq exceed 10 Af-1 sec.-1, and it has been shown that many of these rates are diffusion controlled (92, 113). The parameters used in these calculations, which were carried out according to Debye s theory (41), were a diffusion coefficient of 10-4 sec.-1 (78, 113) and an effective radius of 2.5-3.0 A. (77). The energies of activation observed in e aq reactions are also of the order encountered in diffusion-controlled processes (121). A very recent experimental determination of the diffusion coefficient of e aq by electrical conductivity yielded the value 4.7 0.7 X 10 -5 cm.2 sec.-1 (65). This new value would imply a larger effective cross-section for e aq and would increase the number of diffusion-controlled reactions. A quantitative examination of the rate data for diffusion-controlled processes (47) compared with that of eaq reactions reveals however that most of the latter reactions with specific rates of < 1010 Af-1 sec.-1 are not diffusion controlled. 

Experimental data strongly indicates that anthracite and bituminous coal are electrically anisotropic. Higher resistivity/lower conductivity is observed for specimens oriented perpendicular to the bedding plane relative to those with parallel orientation. 

Abstract Electrical conductivity of agarose gels in 0.15 M KC1 was measured. From the experimental data, a functional relation of solute diffusivity to tissue permeability and solute size was derived. This relationship agreed with the experimental results on macromolecule diffusivity in agarose gel published in the literature. 

From the above equations it is evident that in any calculation of activity coefficients ionic strength is a key parameter and as such it is useful if it can be calculated from experimental data. Ionic strength can be calculated from electrical conductivity measurements using the Babcock equation which is given by Sposito (1989) as... 

Sanchis and coworker [64] in order to insight something about this fact and in order to get confidence about this phenomenon, have used the electric modulus formalism [146], (M = l/e ) to represent the experimental data. The advantages of this kind of representation are evident due to the better resolution observed for dipolar and conductive processes. The imaginary part of M as a function of frequency at 423 K, for both polymers, is shown in Fig. 2.45. The curve corresponding to PTHFM shows a complex behavior at low frequencies, which presumably is the result of the superposition of the two conductive processes. 

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