Specific electric conductivity

The reaction rate is increased by using an entraining agent such as hexane, benzene, toluene, or cyclohexane, depending on the reactant alcohol, to remove the water formed. The concentration of water in the reaction medium can be measured, either by means of the Kad-Eischer reagent, or automatically by specific conductance and used as a control of the rate. The specific electrical conductance of acetic acid containing small amounts of water is given in Table 6. 

The specific electrical conductivity of dry coals is very low, specific resistance 10 ° - ohm-cm, although it increases with rank. Coal has semiconducting properties. The conductivity tends to increase exponentially with increasing temperatures (4,6). As coals are heated to above ca 600°C the conductivity rises especially rapidly owing to rearrangements in the carbon stmcture, although thermal decomposition contributes somewhat below this temperature. Moisture increases conductivity of coal samples through the water film. 

The salt content determines the specific electrical conductivity of the water (see Section 2.2.2). In coastal areas this varies according to tide and time of year. The following average values in ohms per centimeter serve as a guide Narvik roadstead, 33 [7] Helgoland, 27 [7] North Sea, 30 Elbe/Cuxhaven, 100 [7] Elbe/ Brunsbuttelkoog, 580 Elbe/Altona, 1200 Liibeck wharf, 75 Antwerp (Quay 271), 120 Rotterdam Botlek, 240 Tokyo Gulf, 25 [8]. 

When electrical conductivity is used to investigate the compressibility of boride powders at a pressure of 0.19-1.7 X 10 N m , the variation of the specific electrical conductivity x with the relative density 0 (apparent density of the blank/density of the bulk material) is ... 

Dynamic viscosity, mN.s/m2 (20°C) Specific electrical conductivity, s/m (25 Critical temperature, °C Critical density, g/cm3 Critical specific volume, cm3/g Dielectric constant (20° C)... 

True metals alkali, alkaline earth metals, Al, Cu, Ag, Au, etc., having a high specific electrical conductivity (OhnG cm l) k = 105—106 and crystal structures of high symmetry and coordination numbers (CN = 8-12). 

Y. Zhao, J. Wei, R. Vajtai, P. M. Ajayan, E. V. Barrera, Iodine doped carbon nanotube cables exceeding specific electrical conductivity of metals, Scientific Reports 1 83, 2011. 

Babiarz et al. (2001) examined total mercury (Hg) and methyhnercury (Me-Hg) concentrations in the colloidal phase of 15 freshwaters from the upper Midwest and Southern United States. On average, Hg and Me-Hg forms were distributed evenly between the particulate (0.4 jm), colloidal, and dissolved (lOkDa) phases. The amount of Hg in the colloidal phase decreased with increasing specific electric conductance. Furthermore, experiments on freshwater with artificially elevated electric conductance suggest that Hg and Me-Hg may partition to different subfractions of colloidal material. The two colloidal Hg phases act differently with the same type of adsorbent. For example, the colloidal phase Hg correlates poorly with organic carbon (OC) but a strong correlation between Me-Hg and OC was observed. 

At 0° the hydrolysis constant of iodine is 9 xlO-15 The hydrolysis in iodine water is assumed to be I2+H20 HI+HI0. The specific electrical conductivity of iodine water rises very rapidly to about 4xl0 6 and then slowly to about 20Xl0 6 this last effect is supposed to be due to a secondary reaction involving 3I2+3H20=5HI+HI03. 

The specific electrical conductivity 3 K of soln. of potassium iodide and of similar soln. sat. with iodine expressed in reciprocal ohms is for soln. containing n milligram molecules per litre... 

Eole. According to 0. Bock, the specific electrical conductivities of soln. of potassium ydrosulphide and the temp, coefi. of the conductivity at 18°, are ... 

Equation (2) may be used for the rate constant k of a chemical reaction or applied to the diffusion coefficient in liquid or solid phases or to the fluidity of liquids (reciprocal of dynamic viscosity) or to the specific electrical conductivity of semiconductors. 

Fredholm, H. 1942. The specific electrical conductivity of Swedish cow milk, with special reference to the diagnosis of udder disease. Nord. Jordburgsforskning 1942, 195-213. 

Gerber, V. 1927. The significance of the specific electrical conductivity of milk and a new practical procedure for its determination. Z. Untersuch Lebensm. 54, 257-270. 

S. Zimmermann found the specific electrical conductivity of water saturated with nitric oxide to be 36-2x10 . He considers that the soln. in water is in part... 

Important Quantities Connected with Electro Dialysis 3.5.1. Electrical Conductivity of Ion-Exchange Membranes The specific electrical conductivity of an ion selective membrane is given by ... 

The DC conductivity of single crystals and the pressed powder of the synthesized salts has been measured in the temperature range of 77-300 K by four-contact technique. Table 1 presents the values of specific electrical conductivity at room temperature aRT and of conductivity activation energy A calculated on the basis of resistive measurements at various temperatures. Conductivity models applied for the calculation of the A value in each compound are presented and discussed in the next section. 

Specific electrical conductance is the measure of a solution s ability to conduct or carry an electric current and depends on the presence of charged ion species such as calcium, sodium, magnesium chloride, etc. Conductivity measurements are approximately related to total dissolved solids (TDS) in a sample, but since different ions carry different amounts of charge and move at different speeds, their individual contribution to the overall SEC varies. 

Trick J. K., Stuart M., and Reeder S. describe the tools available to the field sampler for the collection of groundwater samples, methods of on-site water quality analysis, and the appropriate preservation and handling ofsamples. The authors discuss the merits of different purge methodologies and show how on-site measurements such as pH, specific electrical conductance (SEC), oxidation—reduction potential (ORP), dissolved oxygen (DO), temperature, and alkalinity can be used to provide a check on subsequent laboratory analyses. Techniques for the preservation and analysis of samples and quality assurance and quality control are also presented. 

Table 1 Equivalent and Specific Electrical Conductivities (A and k) of Some Molten Alkali Halides at 50° above Their Melting Point... 

The specific electrical conductivity of the solutions was measured in a cell with plane-parallel electrodes, the cell constant being 6.5 X 10-2 cm.-1. In all cases the specific electrical conductivity was low (1 X 10-9 ohm-1 cm.-1) hence, it was possible to neglect polarization on electrodes and to use direct current. 

One of the macroscopic techniques for of establishing the transition has been developed by Platikanov and Rangelova [328,329]. It is based on measurement of the longitudinal specific electrical conductivity of a film obtained between two silver cylinders and the specific electrical conductivity of the initial solution as a function of temperature. The comparison of the results allows to find the temperature at which the CBF/NBF transition occurs. Fig. 3.67 plots these results. Line 1 characterising the temperature dependence of the longitudinal specific electrical conductivity Kf for CBF has the same slope as line 3 which refers to the temperature dependence of the specific electrical conductivity k of the bulk phase. The slope of line 2 which is for NBF is much steeper. The cross-point of lines 1 and 2 indicates the temperature of the CBF/NBF transition at the given electrolyte concentration in the initial solution. Here it is 31.6°C. 

Fig. 3.67. Temperature dependence of the specific electrical conductivity of CBF (line 1), NBF (line 2)...

For evaluating the geometric coefficient B it is necessary to determine foam expansion ratio and electrical expansion ratio , which is equal to k[/kF (where kL and kF are the specific electrical conductivities of the solution and the foam, respectively). 

It is only the liquid phase in a foam that possesses electrical conductivity. That is why the specific electrical conductivity of a foam kf (or its specific electrical resistance pF ) depends on the liquid content and on its specific electrical conductivity Kl (or its specific resistance pi)... 

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