Conductivity sodium ions

Ford Motor Co [312] obtained a patent for a method of producing sodium which uses a solid ceramic (P-alumina) that conducts sodium ions as a divider for a two-compartment cell. This method allows low melting sodium salts or salt mixtures to be used to produce sodium [312-315], The cell operates at 200°C and 6 V instead of the conventional 7 V for Downs cells, making sodium at 600°C. The average current efficiency is 100% compared to 85-92% for Downs cells. The power consumption of the process at the same productivity is 20-30% lower than for the Downs cell. This process has, however, not been operated on a large scale because the P-A1203 does not have sufficient lifetime. 

The prime electrochemical difference between the two sodium-beta technologies is the sodium/metal-chloride positive electrode. This component contains a molten secondary electrolyte (NaAlClJ and an insoluble and electrochemically active metal-chloride phase (Fig. 40.1b). The secondary electrolyte is needed to conduct sodium ions from the primary /3"-AI2O3 electrolyte to the solid metal-chloride electrode. Cells using positive electrodes with two transition metal-chlorides, nickel and iron, have been developed. These specific metals were selected based on their insolubility in the molten NaAlCl4 secondary electrolyte. - During discharge, the solid metal-chloride is converted to the parent metal and sodium chloride crystals. The overall cell reactions for these two chemistries are as follows ... 

In the sodium—sulphur battery, patented by Ford, for example, instead of solid electrodes separated by a liquid electrolyte (as in the conventional lead—acid car battery, for example), sodium alumina is used as a solid electrolyte, specifically conducting sodium ions between liquid electrodes of sodium metal and sulphur (Figure 29.1). 

Local anesthetics produce anesthesia by blocking nerve impulse conduction in sensory, as well as motor nerve, fibers. Nerve impulses are initiated by membrane depolarization, effected by the opening of a sodium ion channel and an influx of sodium ions. Local anesthetics act by inhibiting the channel s opening they bind to a receptor located in the channel s interior. The degree of blockage on an isolated nerve depends not only on the amount of dmg, but also on the rate of nerve stimulation (153—156). 

The proposed model for the so-called sodium-potassium pump should be regarded as a first tentative attempt to stimulate the well-informed specialists in that field to investigate the details, i.e., the exact form of the sodium and potassium current-voltage curves at the inner and outer membrane surfaces to demonstrate the excitability (e.g. N, S or Z shaped) connected with changes in the conductance and ion fluxes with this model. To date, the latter is explained by the theory of Hodgkin and Huxley U1) which does not take into account the possibility of solid-state conduction and the fact that a fraction of Na+ in nerves is complexed as indicated by NMR-studies 124). As shown by Iljuschenko and Mirkin 106), the stationary-state approach also considers electron transfer reactions at semiconductors like those of ionselective membranes. It is hoped that this article may facilitate the translation of concepts from the domain of electrodes in corrosion research to membrane research. 

In Chapter 6 we saw that the chemistry of sodium can be understood in terms of the special stability of the inert gas electron population of neon. An electron can be pulled away from a sodium atom relatively easily to form a sodium ion, Na+. Chlorine, on the other hand, readily accepts an electron to form chloride ion, Cl-, achieving the inert gas population of argon. When sodium and chlorine react, the product, sodium chloride, is an ionic solid, made up of Na+ ions and Cl- ions packed in a regular lattice. Sodium chloride dissolves in water to give Na+(aq) and C (aq) ions. Sodium chloride is an electrolyte it forms a conducting solution in water. 

The concentration of the solution within the glass bulb is fixed, and hence on the inner side of the bulb an equilibrium condition leading to a constant potential is established. On the outside of the bulb, the potential developed will be dependent upon the hydrogen ion concentration of the solution in which the bulb is immersed. Within the layer of dry glass which exists between the inner and outer hydrated layers, the conductivity is due to the interstitial migration of sodium ions within the silicate lattice. For a detailed account of the theory of the glass electrode a textbook of electrochemistry should be consulted. 

The structure of / -alumina is shown in Fig. 5. The aluminum and oxygen ions (green and red, respectively) form spinel blocks. The mobile sodium ions (blue) are located in layers between them. The spinel blocks are connected to each other by oxygen ion bridges within the conducting layer. 

This cell reaction necessitates a so-dium-ion-conductive electrolyte. At present, the best and most stable sodium ion conductor is / "-alumina. This electrolyte has sufficient high sodium ion conductivity at temperatures of about 300 °C. The ft"-alumina electrolyte is normally designed as a tube closed at one end with a negative... 

In the Na/S system the sulfur can react with sodium yielding various reaction products, i.e. sodium polysulfides with a composition ranging from Na2S to Na2S5. Because of the violent chemical reaction between sodium and sulfur, the two reactants have to be separated by a solid electrolyte which must be a sodium-ion conductor. / " -Alumina is used at present as the electrolyte material because of its high sodium-ion conductivity. 

The purity of steam can be measured by an increase in electrical conductivity. Testing for sodium ions (Na+) is particularly useful because almost without exception, all BW contains sodium ions. 

It should be possible to purify sodium by electrolysis through a /3-alumina electrolyte this only conducts Na ions, and, therefore, only pure Na should pass through the material. 

The saxitoxins function by binding to a site on the extracellular surface of the voltage-activated sodium channel, interrupting the passive inward flux of sodium ions that would normally occur through the channel while it is in a conducting... 

Because of the high values of conductivity which in individual cases are found at room temperature, such compounds are often called superionic conductors or ionic superconductors but these designations are unfounded, and a more correct designation is solid ionic conductors. Strictly unipolar conduction is typical for all solid ionic conductors in the silver double salts, conduction is due to silver ion migration, whereas in the sodium polyaluminates, conduction is due to sodium ion migration. 

This type of electrolytic cell consists of anodes and cathodes that are separated by a water impermeable ion-conducting membrane. Brine is fed through the anode where chlorine gas is generated and sodium hydroxide solution collects at the cathode. Chloride ions are prevented from migrating from the anode compartment to the cathode compartment by the membrane and this, consequently, leads to the production of sodium hydroxide, free of contaminants like salts. The condition of the membrane during operation requires more care. They must remain stable while being exposed to chlorine and strong caustic solution on either side they must allow, also, the transport of sodium ions and not chloride ions. 

Soft, silvery metal, very reactive. Reacts vigorously with water and air, must be stored under paraffin oil. Used in industry as a strong reducing agent. Reacts with equally aggressive chlorine to form harmless salt known to be essential to life. As all life stemmed from the sea, all life forms require sodium ions, for example, for the conduction of the nerves and for humans to think. In humans (70 kg), 100 g of sodium can be found (as ions). Easy detection makes flames yellow. Used in yellow lamps for street lighting. Sodium ions are widespread, for example, in glass, soap, mineral water, etc. 

To establish the well drainage boundaries and fluid flow patterns within the TFSA-waterflood pilot, an interwell chemical tracer study was conducted. Sodium thiocyanate was selected as the tracer on the basis of its low adsorption characteristics on reservoir rocks (36-38), its low and constant background concentration (0.9 mg/kg) in produced fluids and its ease and accuracy of analysis(39). On July 8, 1986, 500 lb (227 kg) of sodium thiocyanate dissolved in 500 gal (1.89 m3> of injection brine (76700 mg/kg of thiocyanate ion) were injected into Well TU-120. For the next five months, samples of produced fluids were obtained three times per week from each production well. The thiocyanate concentration in the produced brine samples were analyzed in duplicate by the standard ferric nitrate method(39) and in all cases, the precision of the thiocyanate determinations were within 0.3 mg/kg. The concentration of the ion in the produced brine returned to background levels when the sampling and analysis was concluded. 

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