Electrical Conductivity Of Liquid Research Articles

Dissociation of water under pressure.

The dissociation of water under pressure is investigated with a series of ab initio molecular dynamics simulations at thermodynamic conditions close to those obtained in shock wave experiments. We find that molecular dissociation occurs via a bimolecular process similar to ambient conditions, leading to the formation of short-lived hydronium ions. Up to twofold compression and 2000 K, the oxygen diffusion coefficient is characteristic of a fluid. Our findings do not support models used to estimate the liquid electrical conductivity and interpret Raman spectra that assume the presence of free protons.

Space charge density in dielectric and conductive liquids flowing through a glass pipe

Flow electrification phenomena in the case of conductive and dielectric liquids flowing through an insulating pipe are compared. A theoretical model, which takes into account the development time of the diffuse layer in the case of a laminar flow, is compared with streaming current measurements. Experiments are conducted with water (electrical conductivity 0.2<σ<1.4mS/m) and heptane (53<σ<1010pS/m) flowing through a 32μm-radius glass pipe. Evolution of the space charge density at the wall ρw in function of the liquid conductivity σ is analysed. Results show that the intensity of flow electrification depends mainly on the space charge density at the wall and the liquid electrical conductivity.

Monodisperse Electrosprays of Low Electric Conductivity Liquids in the Cone-Jet Mode

An experimental investigation was performed on electrosprays of low electric conductivity liquids (heptane with different amounts of an antistatic additive) that were operated in the cone-jet mode. The effects of liquid flow rate, applied voltage, and liquid electric conductivity on droplet size and spray monodispersity were systematically investigated. The droplet size was found to be dominantly controlled by the liquid flow rate and secondarily by the applied voltage. It showed no dependence on capillary size. For a given liquid, stable and monodisperse electrosprays could be established only within certain ranges of liquid flow rates and applied voltages, that defined a cone-jet domain. This domain was affected by the electric conductivity of the liquid. As the liquid electric conductivity increased, the domain shifted toward smaller flow rates which implies that smaller droplets were generated in the spray. An increase in the capillary diameter caused a narrowing of this domain. Outside the cone-jet domain, electrosprays were unstable and polydisperse with different instability patterns that depended on the applied voltage and the liquid flow rate. Experiments also showed that the droplet size and the spray monodispersity were independent of the electrode configuration, as long as the electrospray was operated at the onset voltage condition, that is defined as the minimum voltage at which the cone-jet mode was established. By using dimensional analysis the controlling variables were combined into a few dimensionless groups and an empirical fit was derived and was shown to correlate well all the experimental data.

Electrospraying of conducting liquids for monodisperse aerosol generation in the 4 nm to 1.8 μm diameter range

An electrospraying system operated in the cone-jet mode is shown to produce monodisperse droplets in a wide size range and with good monodispersity. These highly charged droplets are rapidly discharged in a radioactive neutralizer. The produced droplet size can be further reduced by the evaporation process without experiencing the Rayleigh breakup. The experiment is performed using sucrose solutions and the liquid electrical conductivity is controlled by adding small amounts of nitric acid. The size distribution is quite monodisperse having a geometrical standard deviation of 1.1. The mean droplet size produced can be varied from 40 nm to 1.8 μm by changing the liquid feed rate and electrical conductivity. Using 0.1% sucrose concentration solution, the residue particle size is reduced by a factor of ten, in the range from 4 nm to 0.18 μm. The parameters affecting the particle size distribution, the measured spraying current, and the operating envelope have also been obtained and quantified.

Specific charge of induction electrified sprays

The charge per unit volume, or specific charge, of an induction electrified spray has been measured. Two different models are presented to evaluate this charge. One is based on Maxwell's equations, and the other considers an equivalent circuit. As the charging process is dependent on the hydrodynamic rupture of the liquid jet, a simplified model of this process is formulated. Theoretical predictions are compared with the experimental results for different values of the liquid electrical conductivity, spraying air flow rate and liquid flow rate.

Ice physical properties, structural characteristics and stratigraphy in Hobson’s Choice Ice Island and implications for the growth history of East Ward Hunt Ice Shelf, Canadian High Arctic

AbstractHobson’s Choice Ice Island is a tabular iceberg that calved in 1982-83 from East Ward Hunt Ice Shelf, N.W.T., Canada. Four ice cores have been analyzed for ice-crystal size, structure and fabric, bulk density, liquid electrical conductivity, δ18O and tritium. This has enabled a complete characterization of the physical properties and the structural characteristics of the ice-shelf component of Hobson’s Choice Ice Island and the first ever study of the stratigraphy and growth history of East Ward Hunt Ice Shelf. The δ18O values range from -34.6 toand indicate that all the ice is derived directly and/or indirectly from precipitation. High tritium values occur only in the lowermost 5 m of the ice shelf in a layer named stratum B. The tritium is anthropogenic and indicates bottom accretion of fresh-water ice since 1952, most likely from fresh water flowing out of Disraeli Fiord below the eastern ice shelf. Above this deepest and youngest ice layer is a 35-38 m thick, unconformable layer (stratum A) comprising three ice types: iced-firn, slush ice and lake ice. This depositional-superimposed ice represents past surface accumulation, which, according to δ18O and ice-crystal structure and size variations, occurred in three major periods, each interrupted by major ablation periods. Fresh water flowing out of Disraeli Fiord below the ice shelf during those warm intervals was the most likely agent responsible for the ablation and eventual complete loss of the original sea-ice platform on which stratum A initially accumulated. The three sub-strata of stratum A vary in thickness from core to core and suggest that there has been an inversion of relief during each ablation period. The different properties and occurrences of the three superimposed ice types are due primarily to past topographic variability.

Ice physical properties, structural characteristics and stratigraphy in Hobson’s Choice Ice Island and implications for the growth history of East Ward Hunt Ice Shelf, Canadian High Arctic

AbstractHobson’s Choice Ice Island is a tabular iceberg that calved in 1982-83 from East Ward Hunt Ice Shelf, N.W.T., Canada. Four ice cores have been analyzed for ice-crystal size, structure and fabric, bulk density, liquid electrical conductivity, δ18O and tritium. This has enabled a complete characterization of the physical properties and the structural characteristics of the ice-shelf component of Hobson’s Choice Ice Island and the first ever study of the stratigraphy and growth history of East Ward Hunt Ice Shelf. The δ18O values range from -34.6 toand indicate that all the ice is derived directly and/or indirectly from precipitation. High tritium values occur only in the lowermost 5 m of the ice shelf in a layer named stratum B. The tritium is anthropogenic and indicates bottom accretion of fresh-water ice since 1952, most likely from fresh water flowing out of Disraeli Fiord below the eastern ice shelf. Above this deepest and youngest ice layer is a 35-38 m thick, unconformable layer (stratum A) comprising three ice types: iced-firn, slush ice and lake ice. This depositional-superimposed ice represents past surface accumulation, which, according to δ18O and ice-crystal structure and size variations, occurred in three major periods, each interrupted by major ablation periods. Fresh water flowing out of Disraeli Fiord below the ice shelf during those warm intervals was the most likely agent responsible for the ablation and eventual complete loss of the original sea-ice platform on which stratum A initially accumulated. The three sub-strata of stratum A vary in thickness from core to core and suggest that there has been an inversion of relief during each ablation period. The different properties and occurrences of the three superimposed ice types are due primarily to past topographic variability.

A new differential method of measuring liquid electrical conductivity

A new differential method of measuring liquid electrical conductivity

Example et application d'une méthode de mesure d'impédance électrique: évolution de la conductivité électrique d'une pâte de ciment au cours de sa prise

A method for determining conductivity of solid state electrolytes by drawing complex impedance diagrams, is used to follow the evolution of the conductivity of pure cement paste during the hydration state. The report underlines: - the reliability of this method which offers the possibility of avoiding the polarization effects disturbing this type of measurements; - the general nature of this technique which is also applicable to the determination of the electrical conductivity of liquids or solids, effective or poor conductors. This research was undertaken during work on the corrosion of the steel wires for prestressed concrete.

Density and electrical conductivity measurements of conducting liquids at high temperatures and pressures—application to tellurium

Experimental methods are presented for the measurement of mass density and electrical conductivity of liquids. Density is measured by a new thermometrical method using a resistive detector, and conductivity by a standard four probe method. An application is given to tellurium and density–conductivity data are obtained in the temperature range of 450°–800°C and the pressure range of 30–1500 bars.

Electrical conductivity of molten FeNiSC core mix

The electrical conductivity of liquid (Fe 90Ni 10) 3S 2 saturated with 2.6 weight percent carbon averages 2.7·10 5 mho/m at 1000°C and zero pressure. This may imply a slightly lower electrical conductivity for the earth's core than that obtained by extrapolating the properties of pure liquid iron and solid iron alloys to core pressures and temperatures. Although a sulphur-rich core would have a smaller proportion of sulphur, the effect of lowering the sulphur content of the FeNiSC liquid to about 15 weight percent would be unlikely to increase the conductivity above 5·10 5 mho/m.

Electroslag remelting with all-fluoride low conductivity slags

The electrical conductivity of liquids in the composition ranges CaF2 + 0 to 12 wt pct AIF3; CaF2 + 0 to 20 wt pct LaF3; and CaF2 + 0 to 30 wt pct YF3 has been determined at 1500° and 1600°C. It is deduced from the conductivities and the form of the phase diagrams of these systems that CaF2 + 20 wt pct YF3 is the optimum all-fluoride composition for electroslag melting or welding high melting point materials. It is demonstrated that pure iron, AISI 4340, AISI 321, and Hastelloy-X may all be electroslag melted without arcing through this slag using 60 Hz power. However, the initial postulate is confirmed in that only those materials with liquidus temperatures below that of the phase precipitated on freezing the slag can be made into ingots with good surface quality. The use of this slag in electroslag welding pure iron is investigated. It is inferred from the results that the slag composition chosen could probably be used to electroslag weld thick sections of titanium.

Electrical conductivity of liquid and saturated vapor of bismuth(III) chloride and mercury(II) chloride to their critical temperatures

Electrical conductivity of liquid and saturated vapor of bismuth(III) chloride and mercury(II) chloride to their critical temperatures

The electrical conductivity of liquid and solid nitrogen dioxide

The electrical conductivity of liquid and solid nitrogen dioxide

The effect of pressure on the electrical conductivity of liquids

The effect of pressure on the electrical conductivity of liquids

Scientific Serials

American journal of Science, September.—Rocky mountain protaxis and the post-cretaceous mountain-making along its course, by J. D. Dana.—The magneto-optical generation of electricity, by Dr. Sheldon. It is well known that, by using proper conditions, a beam of plane polarized light may be rotated by an electromagnet, and that a reversal of the current causes the plane to be rotated in the opposite direction. A rapidly alternating current thus produces a rapid swinging to and fro of the plane of light. The author has conducted the converse experiment, and by oscillating the plane of polarization through 90° about 300 times per second, has produced an alternating current.—Contributions to mineralogy, No. 49, by F. A. Genth, with crystallographic notes by S. L. Penfield. The results are given of the examination of some specimens of ferric sulphate from Mina de la Compania, Chili.—Chalcopyrite crystals from the French Creek Iron Mines, St. Peter, Chester County, Pa., by S. L. Penfield.—Koninckina and related genera, by Dr. Charles E. Beecher.—The effect of pressure on the electrical conductivity of liquids, by C. Barus. It is shown that, both in the case of mercury and a concentrated solution of zinc sulphate, the effect of isothermal compression is a decrement of resistance nearly proportional to pressure, and from this fact the deduction is made that the immediate effect of rise of temperature is a decrement of specific resistance.—Notice of two new iron meteorites from Hamilton County, Texas, and Puquois, Chili, by Edwin E. Howell. Analyses of the two meteorites are given.—The Cretaceous of Manitoba, by J. B. Tyrrell.—On mordenite, by Louis V. Pirsson.—Geology of Mon Louis Island, Mobile Bay, by Daniel W. Langdon, Jun.—On Leptænisca, a new genus of Brachiopod from the Lower Helderberg group, by Dr. Charles E. Beecher.—North American species of Strophalosia, by the same author.—Notes on the microscopic structure of oolite, with analyses, by Erwin H. Barbour and Joseph Torrey, Jun.

Measurement of the electrical conductivity of liquids hitherto supposed to be insulators

Measurement of the electrical conductivity of liquids hitherto supposed to be insulators