Movable short-circuit technique to extract the relative permittivity of materials from a coaxial cell

We studied the effect of ethanol on the electrical and ion transport properties of dog tracheal epithelium using Ussing's short-circuit technique. There was a significant reduction of short-circuit current and electrical potential difference and a tendency of electrical resistance to increase in response to increasing concentrations of ethanol in the bathing solutions. Threshold changes in the electrical properties were noted at an ethanol concentration of 3.3 microliter/ml (260 mg/100 ml). Ethanol did not produce these changes in electrical properties when Cl- and Na+ were substituted in the bathing media with either choline or SO2-(4). In five paired tissue preparations, ethanol (13.3 microliters/ml) significantly reduced the net flux of Cl- toward the lumen from 2.68 +/- 0.62 to 1.00 +/- 0.69 (SE) mu eq X cm-2 X h-1, due primarily to a reduced unidirectional flux of Cl- from submucosa to lumen. These observations demonstrate that ethanol has an effect on the ion transport and electrical properties of dog tracheal epithelium at concentrations that may be of clinical relevance.

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An Open- and Short-Circuit Technique for Analyzing Electronic Circuits

IEEE Transactions on Education ◽

10.1109/te.1987.5570587 ◽

1987 ◽

Vol E-30 (1) ◽

pp. 55-56 ◽

Cited By ~ 3

Author(s):

Kai S. Yeung

Keyword(s):

Short Circuit ◽

Electronic Circuits ◽

Circuit Technique

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The Relation between Salt and Ionic Transport Coefficients

The Journal of General Physiology ◽

10.1085/jgp.49.4.655 ◽

1966 ◽

Vol 49 (4) ◽

pp. 655-662 ◽

Cited By ~ 14

Author(s):

Ora Kedem ◽

Alexander Leaf

Keyword(s):

Reflection Coefficient ◽

Electric Field ◽

Short Circuit ◽

Transport Coefficients ◽

Ionic Transport ◽

Permeability Barrier ◽

Neutral Component ◽

Charged Membrane ◽

The Individual ◽

Circuit Technique

The reflection coefficient was originally introduced by Staverman to describe the movement of nonelectrolytes through membranes. When this coefficient is extended to salts, one has a choice of defining this term for the whole salt moving as a single electrically neutral component or for the individual ions of the salt. The latter definition is meaningful only in the absence of an electric field across the permeability barrier. This condition may be achieved with the voltage clamp or short-circuit technique and is especially useful in dealing with biological systems in which one rarely has only a single salt or even equal concentrations of the major anion and cation. The relations between the transport coefficients for the salt and its individual ions are derived. The special conditions which may result in negative osmosis through a charged membrane in the presence of a salt are discussed.

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Ion Transport and Short-Circuit Technique

Current Topics in Membranes and Transport ◽

10.1016/s0070-2161(08)60860-6 ◽

1975 ◽

pp. 217-270 ◽

Cited By ~ 9

Author(s):

Warren S. Rehm

Keyword(s):

Ion Transport ◽

Short Circuit ◽

Circuit Technique

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Structural Imperfections in thin Oxide Films Formed on Some Fe- and Ni-Base Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069545 ◽

1970 ◽

Vol 28 ◽

pp. 510-511

Author(s):

L. P. Lemaire ◽

D. E. Fornwalt ◽

F. S. Pettit ◽

B. H. Kear

Keyword(s):

Oxide Scale ◽

Oxidation Process ◽

Short Circuit ◽

Protective Oxide ◽

Protective Oxide Scale ◽

Thin Oxide Films ◽

Diffusion Paths ◽

Oxidation Resistant ◽

Structural Imperfections ◽

Short Circuit Diffusion

Oxidation resistant alloys depend on the formation of a continuous layer of protective oxide scale during the oxidation process. The initial stages of oxidation of multi-component alloys can be quite complex, since numerous metal oxides can be formed. For oxidation resistance, the composition is adjusted so that selective oxidation occurs of that element whose oxide affords the most protection. Ideally, the protective oxide scale should be i) structurally perfect, so as to avoid short-circuit diffusion paths, and ii) strongly adherent to the alloy substrate, which minimizes spalling in response to thermal cycling. Small concentrations (∼ 0.1%) of certain reactive elements, such as yttrium, markedly improve the adherence of oxide scales in many alloy systems.

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