Conductivity factor

Abstract: Recent research has demonstrated that field soil salinity can be inferred from four-electrode soil electrical conductivity (ECa), if the soil profile is near "field capacity" and calibration curves, based on saturation extract salinity (ECe), are available. To extend the use of this field method to arbitrary water contents, we studied EC in the laboratory as a function of water content and in situ soil water conductivity (ECw). We collected undisturbed cores of four soil types (fsl, vfsl, 1, cl) using Lucite column inserts, which were tapped for later insertion of electrodes. The cells were equilibrated with waters of a desired EC,r and, using a pressure membrane apparatus, adjusted to a desired Values of ECa were calculated for each ECW equilibration from measured four-electrode resistances and an appropriate cell constant. Our results indicated that over the -range of practical concern, ECa = (transmission coefficient) x x ECw + surface conductivity. This relationship is derived using a simple capillary model, which assumes that liquid phase and surface conductivities (via exchangeable cations) behave as resistors in parallel. Additional Index Words: soil electrical conductivity, soil salinity, surface conductance. View complete article To view this complete article, insert Disc 3 then click button8

Abstract: Two parallel metallic rods were used as a wave guide to measure the dielectric constant and electrical conductivity of soils having different electrical conductivities but the same water content. Measurements showed that the two parameters were sufficiently independent to permit simultaneous determinations of water content and bulk electrical conductivity.

Abstract: Foreword. Introduction. The Preparation of the Thermal Conductivity Tables. The Effect of Radiative Heat Transfer. Thermal Conductivity of Monoatomic Substances. Thermal Conductivity of Simple Diatomic Fluids. Thermal Conductivity of Air. Thermal Conductivity of Inorganic Fluids. Thermal Conductivity of Ordinary and Heavy Water. Thermal Conductivity of Alkali Metals. Correlations for Thermal Conductivity of Methane Series of Normal Hydrocarbons in Gaseous State at a Pressure of 0.1 MPa. Thermal Conductivity of Organic Fluids C1. Thermal Conductivity of Organic Fluids C2. Thermal Conductivity of Organic Fluids C3. Thermal Conductivity of Organic Fluids C4. Thermal Conductivity of Organic Fluids C5. Thermal Conductivity of Organic Fluids C6. Thermal Conductivity of Organic Fluids C7. Thermal Conductivity of Organic Fluids C8. Thermal Conductivity of Organic Fluids C9. Thermal Conductivity of Organic Fluids C10. Thermal Conductivity of Organic Fluids C11. Thermal Conductivity of Organic Fluids C12. Thermal Conductivity of Organic Fluids C13. Thermal Conductivity of Organic Fluids C14. Thermal Conductivity of Organic Fluids C15. Thermal Conductivity of Organic Fluids C16. Thermal Conductivity of Organic Fluids C17. Thermal Conductivity of Organic Fluids C18. Thermal Conductivity of Organic Fluids C19. Thermal Conductivity of Organic Fluids C20. Thermal Conductivity of Organic Fluids C21. Thermal Conductivity of Organic Fluids C22. Thermal Conductivity of Organic Fluids C23. Thermal Conductivity of Organic Fluids C24. Thermal Conductivity of Organic Fluids C25. Thermal Conductivity of Isotope-Containing Compounds. References. Index.

Abstract: The most accurate values to date were determined for conductivity of water from 0-100°C, permitting new determination of high-temperature hydroxide ion equivalent conductance. These values were incorporated into a fundamental water coefficient table including hydroxide and hydrogen ion mobilities, water ionization constant, density, conductivity, and resistivity. The conductivity/resistivity values were measured with a multiple-pass, closed, recirculating flow conductivity system, with improved multiple resistance temperature device measurement, and improved analysis of temperature and impurity effects. An accurate conductivity knowledge is necessary to understand water-limiting processes and to facilitate the analysis of trace ionic impurities in water.