Potentiometric measurement with a Kelvin probe: Contactless measurement of chloride ions in aqueous electrolyte

AbstractElectrochemically reversible redox couples that embrace more electron transfer at a higher potential are the eternal target for energy storage batteries. Here, we report a four-electron aqueous zinc-iodine battery by activating the highly reversible I2/I+ couple (1.83 V vs. Zn/Zn2+) in addition to the typical I−/I2 couple (1.29 V). This is achieved by intensive solvation of the aqueous electrolyte to yield ICl inter-halogens and to suspend its hydrolysis. Experimental characterization and modelling reveal that limited water activity and sufficient free chloride ions in the electrolyte are crucial for the four-electron process. The merits of the electrolyte also afford to stabilize Zn anode, leading to a reliable Zn-I2 aqueous battery of 6000 cycles. Owing to high operational voltage and capacity, energy density up to 750 Wh kg−1 based on iodine mass was achieved (15–20 wt% iodine in electrode). It pushes the Zn-I2 battery to a superior level among these available aqueous batteries.

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Effect of Anions (Cl−, SO2−4) on the Interfacial Properties of Akaganeite (β-FeOOH) in Aqueous Electrolyte Solutions

Adsorption Science & Technology ◽

10.1177/026361748800500402 ◽

1988 ◽

Vol 5 (4) ◽

pp. 257-279 ◽

Cited By ~ 2

Author(s):

K.M. Parida

Keyword(s):

Aqueous Electrolyte ◽

Surface Acidity ◽

Aqueous Media ◽

Electrolyte Solutions ◽

Chloride Ions ◽

Point Of Zero Charge ◽

Surface Complexes ◽

Solution Interface ◽

Adsorption Data ◽

Titration Data

The point of zero charge (pHpzc) of the sample (β-FeOOH) is shifted from 7.50 to 8.20 and 8.55, respectively, in KCl and K2SO4 electrolyte media. Intrinsic surface acidity and complexation constants have been calculated by single and double extrapolation methods using Potentiometrie titration data obtained for different concentrations of KCl and K2SO4 in aqueous media. Complexation con stants for K+, Cl− and SO2−4 have also been calculated from adsorption data by the same two methods. Close agreement exists between the two sets of values. Chloride ions form SOH2−4 – Cl− surface complexes on a β-FeOOH surface, whereas sulphate ions form two types of surface complex i.e. SOH+2 – SO2−4 and SOH+2 – SO4H−. Various parameters such as σ0, ψ0, ψd, dσ0/dψ0, etc. associated with the electrical double layer at the oxide/aqueous KCl and K2SO4 electrolyte solution interface have been calculated from Potentiometrie and adsorption data, and are discussed.

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High-pressure high-temperature cell for potentiometric measurement in aqueous electrolyte solutions

Fresenius Zeitschrift für Analytische Chemie ◽

10.1007/bf00594060 ◽

1984 ◽

Vol 317 (2) ◽

pp. 118-120 ◽

Cited By ~ 5

Author(s):

P. Becker ◽

B. A. Bilal

Keyword(s):

High Pressure ◽

High Temperature ◽

Aqueous Electrolyte ◽

Electrolyte Solutions ◽

Aqueous Electrolyte Solutions ◽

High Pressure High Temperature ◽

Potentiometric Measurement

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Junction of the Epithelium and Lamina Propria of the Bovine Rumen Mucosa

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100060350 ◽

1967 ◽

Vol 25 ◽

pp. 68-69

Author(s):

Al W. Stinson

Keyword(s):

Osmium Tetroxide ◽

Squamous Epithelium ◽

Short Chain Fatty Acids ◽

Chloride Ions ◽

Fermentation Products ◽

Ruminant Species ◽

Protective Shield ◽

Stratified Squamous Epithelium ◽

Lead Hydroxide ◽

Acetic Acids

The stratified squamous epithelium which lines the ruminal compartment of the bovine stomach performs at least three important functions. (1) The upper keratinized layer forms a protective shield against the rough, fibrous, constantly moving ingesta. (2) It is an organ of absorption since a number of substances are absorbed directly through the epithelium. These include short chain fatty acids, potassium, sodium and chloride ions, water, and many others. (3) The cells of the deeper layers metabolize butyric acid and to a lesser extent propionic and acetic acids which are the fermentation products of rumen digestion. Because of the functional characteristics, this epithelium is important in the digestive process of ruminant species which convert large quantities of rough, fibrous feed into energy.Tissue used in this study was obtained by biopsy through a rumen fistula from clinically healthy, yearling holstein steers. The animals had been fed a typical diet of hay and grain and the ruminal papillae were fully developed. The tissue was immediately immersed in 1% osmium tetroxide buffered to a pH of 7.4 and fixed for 2 hrs. The tissue blocks were embedded in Vestapol-W, sectioned with a Porter-Blum microtome with glass knives and stained with lead hydroxide. The sections were studied with an RCA EMU 3F electron microscope.

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Factors Influencing the Separation of Glu-Plasminogen Affinity Forms I and II by Affinity Chromatography

Thrombosis and Haemostasis ◽

10.1055/s-0038-1661211 ◽

1984 ◽

Vol 52 (03) ◽

pp. 347-349 ◽

Cited By ~ 6

Author(s):

Daan W Traas ◽

Bep Hoegee-de Nobel ◽

Willem Nieuwenhuizen

Keyword(s):

Affinity Chromatography ◽

Dissociation Constants ◽

Ionic Composition ◽

Chloride Ions ◽

Factors Influencing ◽

Two Factors ◽

Human Plasminogen

SummaryNative human plasminogen, the proenzyme of plasmin (E. C. 3.4.21.7) occurs in blood in two well defined forms, affinity forms I and II. In this paper, the feasibility of separating these forms of human native plasminogen by affinity chromatography, is shown to be dependent on two factors: 1) the ionic composition of the buffer containing the displacing agent: buffers of varying contents of sodium, Tris, phosphate and chloride ions were compared, and 2) the type of adsorbent. Two adsorbents were compared: Sepharose-lysine and Sepharose-bisoxirane-lysine. Only in the phosphate containing buffers, irrespective of the type of adsorbent, the affinity forms can be separated. The influence of the adsorbent can be accounted for by a large difference in dissociation constants of the complex between plasminogen and the immobilized lysine.

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