Electrical Conductivity of Sulfur

Figures 5 and 6 present the electrical conductivity of sulfuric acid solutions (51,52). For sulfuric acid solutions in the 90—100% H2SO concentration range, the electrical conductivity measurements reported by Reference 52 are beheved to be the best values other conductivity data are also available...

Hauver concluded that pressure-time measurements with a sulfur transducer in contact with detonating Baratol gave clear evidence of an initial pressure spike, and lends addnl confirmation to the hydro-dynamic theory of deton proposed by von Neumann and others. The sulfur transducer appeared capable of good resolution over that portion of the pressure-time curve corresponding to the reaction zone, and may offer a method for investigating the reaction process Refs 1) S. Joigneau J. Thouvenin, "Electrical Conductivity of Sulfur Under the Action of a Shock Wave , CR 246, 3422-25 (1958) 2) G.E. Hauver,... 

No information has been found in the literature on the electrical conductivities of sulfur-phosphorus mixtures. The following studies do not cover the entire sulfur-phosphorus system they are limited to measurements on sulfur, P4S3, and two intermediate compositions in the sulfur-rich region of the system. 

Table 3.4 provides data about the specific and equivalent electrical conductivities of sulfuric acid solutions of various concentrations, expressed in different units [2]. 

The potassium combines with the sulfur to form potassium sulfate, which condenses as a soHd primarily in the electrostatic precipitator (ESP) or baghouse. The recovered potassium sulfate is then deUvered to a seed regeneration unit where the ash and sulfur are removed, and the potassium, in a sulfur-free form such as formate or carbonate, is recycled to the MHD combustor. It is necessary also to remove anions such as Cf and E which reduce the electrical conductivity of the generator gas flow. These are present in the coal ash in very small and therefore relatively harmless concentrations. As the seed is recycled, however, the concentrations, particularly of CF, tend to build up and to become a serious contaminant unless removed. 

Electrical Conductivity of Liquid Sulfur and Sulfur-Phosphorus Mixtures... 

Sulfur vapor consists of a mixture of species that includes S8, S6, S4, and S2 (which like 02 is paramagnetic). Because the S8 molecule is nonpolar, it is soluble in liquids such as CS2 and C6H6. Selenium also consists of cyclic molecules that contain eight atoms, and tellurium is essentially metallic in character. In their vapors, several species are found that contain 2, 6, or 8 atoms. Both are useful as semiconductors, and selenium has been used in rectifiers. Because the electrical conductivity of selenium increases as the intensity of illumination increases, it has been used to operate electrical switches that open or close as a light beam is broken. Selenium was also used in light meters, but other types of meters are now available that are more sensitive. Table 15.1 gives a summary of the properties of the group VIA elements. 

A new solid state chemical sensor for sulfur dioxide utilizing a sodium sulfate/rare earth sulfates/silicon dioxide electrolyte has been developed. The addition of rare earth sulfates and silicon dioxide to the sodium sulfate electrolyte was found to enhance the durability and electrical conductivity of the electrolyte. The electrolyte exhibits a Nernstian response in the range of SC gas concentrations from 30 ppm to 1 %. 

Upon discharge sodium ions diffuse through the sodium-conducting /J- or -alumina or NASICON -> solid electrolyte. On the outer surface of the solid electrolyte they react with molten sulfur and/or low valency sulfide anions forming negatively charged polysulfide anions. The rather low electric conductivity of molten sulfur is improved by addition of tetracyanoethylene... 

Fig. A.5. Electrical conductivity versus mass% H2SO4 in sulfuric acid. Source Roughton, J.E. (1951) The electrical conductivity of aqueous solutions of sulphuric acid from 25°C to 155°C, J. Appl. Chem.,1, Supplementary Issue, No. 2., 141 144.

Special considerations zinc oxide is crosshnking agent carbon black is a more efficient UV stabilizer in sulfur-cured SBR than in radiation or peroxide cured " vulcanization conditions affects electric conductivity of carbon black filled SBR solvent diffusion and swelling rate decrease as concentration of carbon black increases ... 

Fig. 5 Temperature dependence of the electrical conductivity of very pure liquid sulfur [123]...

Hertlein (US) in 1896 measured refraction, viscosity, and electrical conductivity of aqueous potassium tri-, tetra-, and pentathionates and decided in favor of uiibranched structures, and so did Martin and Metz (171) in 1924 on the basis of thermochemical measurements. Spacu and Popper (208) in 1939 reported the refraction of sodium tetrathionate Grinberg (186) has later commented on the ionic refraction of tetra thionate as indicating negative charge on the divalent sulfur atoms. However, from Hertlein s measurements the increments per sulfur atom, from tri-to tetra-thionate and tetra- to pentathionate, are about 9 cm3. This is the same as in other series, for example, in the polysulfur dichlorides (72) where the sulfur atoms are hardly negative. 

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