The Isotope Effect of a Direct Electric Current through Liquid and Solid Metals

1956 ◽  
Vol 11 (1) ◽  
pp. 71-75
Author(s):  
E. Haeffner ◽  
Th. Sjöborg ◽  
S. Lindhe
Keyword(s):  
Liquid Metal ◽  
Electric Current ◽  
Isotope Effect ◽  
Direct Current ◽  
Capillary Tube ◽  
Isotope Separation ◽  
Direct Electric Current ◽  
Separation Effect ◽  
A Current

The isotope separation effect of a direct electric current in a liquid metal is demonstrated by passing a current through mercury, which is enclosed in a capillary tube. The second part of the paper deals with an attempt of establishing an isotope effect when a direct current is passed through an uranium wire.

scholarly journals The cataphoresis of gas bubbles in water

1924 ◽  
Vol 106 (737) ◽  
pp. 315-340 ◽  
Keyword(s):  
Electric Current ◽  
Capillary Tube ◽  
Gas Bubbles ◽  
Air Bubbles ◽  
Glass Capillary ◽  
Capillary Tubes ◽  
Quantitative Results ◽  
A Current

The first observations on the electrification of liquid-gas interfaces were ode by Quincke (‘ Pogg. Ann.,’ vol. 113, p. 513 (1861)). He found that the sage of an electric current through a capillary tube containing water caused movement of the surface of the latter, which was exactly proportional to quantity of electricity passed. He also noted that the passage of a current though a liquid containing gas bubbles caused the latter to move towards an electrode. In his experiments the motion of these air bubbles was inestigated in narrow glass capillary tubes, and the bubbles were found to move towards the anode when submerged in water, but towards the cathode en the water was replaced by turpentine. Further work on the electrification of gas bubbles was carried out by Taggart (‘ Phil. Mag.,’ vol. 27, p. 297 (1914) ; vol. 28, p. 367 (1914)). The rrow capillary tubes used by Quincke for this purpose are not very satisfactory, ache bubble tends to stick to the sides of the tube, making it almost impossible obtain quantitative results.

scholarly journals Charge carriers drift induced THz amplification in dual-layer graphene structure

2021 ◽  
Vol 2015 (1) ◽  
pp. 012094
Author(s):  
I.M. Moiseenko ◽  
V.V. Popov ◽  
D.V. Fateev
Keyword(s):  
Electric Current ◽  
Direct Current ◽  
Spatial Dispersion ◽  
Charge Carriers ◽  
Frequency Range ◽  
Direct Electric Current ◽  
The Real ◽  
Layer Graphene

Abstract The terahertz plasmon amplification in structure based on graphene with spatial dispersion of its hydrodynamic conductivity is investigated theoretically. The spatial dispersion of graphene conductivity is related to accounting of charge carriers pressure forces and direct current in graphene. It was shown that the real part of graphene conductivity becomes negative at THz frequency range due to direct electric current in graphene.

scholarly journals Stimulation of Osteogenesis by Direct Electric Current (Review)

2019 ◽  
Vol 25 (3) ◽  
pp. 185-191
Author(s):  
E. N. Ovchinnikov ◽  
M. V. Stogov
Keyword(s):  
Stem Cells ◽  
Electric Current ◽  
Direct Current ◽  
English Language ◽  
Direct Electric Current ◽  
Metal Implants ◽  
Electromagnetic Stimulation ◽  
Analytical Review ◽  
Differentiation And Proliferation ◽  
Stimulation Of

Background. Stimulation of osteogenesis in the treatment of certain orthopedic and trauma pathologies is a necessary element to ensure the best clinical outcome. The purpose of the present analytical review is to analyze the literature data in respect of evaluating the approaches and possibilities to stimulate osteogenesis using direct current. Methods. The search for literature data was performed in the open electronic databases of scientific literature PubMed and eLIBRARY under the following keywords and their combinations: “osteogenesis”, “reparative osteogenesis”, “direct electric current”, “orthopaedics”, “traumatology”, “electric current” (in Russian as well as in English language ). Results. According to some fundamental research, the stimulating effect of direct current lies is both in stimulating differentiation and proliferation of osteoblasts, and in stimulating differentiation of stem cells, mainly mesenchymal stem cells of bone marrow and adipose tissue, in the process of osteogenesis. The following stimulating technologies were developed and clinically tested to date: 1 — direct exposure of bone to the direct current; 2 — capacitive coupled stimulation; and 3 — inductive coupled (electromagnetic) stimulation. Analysis of clinical practice demonstrated that the first technology is most effective in terms of osteoreparation, but less safe than technology 2 and 3. It should be noted that there are no clear indications and modes of application for the abovementioned methods. Based on the data collected in the present analysis, technology 1 is considered by authors as the most promising. Safety of technology 1 can be enhanced by application of metal implants as electrodes in case those are planned to be used for medical reasons: wires, rods, staples, fixators, etc. Conclusion. Use of electric current to stimulate bone formation is a promising method which requires clarification in respect of indications and application modes.

scholarly journals Electro-physiological researches.—Fourth memoir

1851 ◽  
Vol 5 ◽  
pp. 629-629
Keyword(s):  
Electric Current ◽  
Direct Current ◽  
The Other ◽  
Electric Currents ◽  
Physiological Action ◽  
Other Hand ◽  
A Current ◽  
Contrary Direction ◽  
Mixed Nerve

In the prosecution of his inquiries on the physiological action of electric currents, the author found it necessary to employ an apparatus, which was expressly made for him by M. Bréguet, adapted to the delicate appreciation of the intensity of the force of the mus­cular contractions excited by those currents; of which apparatus he gives a minute description, illustrated by a drawing. He was thus enabled to institute an exact comparison between the contrac­tions caused by the direct, and those by the reverse currents, both at the commencement and at the termination of their action. The following are the general conclusions he deduces from the experi­ments thus conducted. 1. The passage of the electric current through a mixed nerve pro­duces a variation in the excitability of the nerve, differing essen­tially in degree, according to the direction of the current through the nerve. This excitability is weakened and ultimately destroyed; and this takes place more or less rapidly according as the direct current , that is, a current circulating through the nerve from the centre to the periphery, is more or less intense. On the other hand, by the passage of the same current in the contrary direction, that is, from the periphery to the centre, or the inverse current , the ex­citability is preserved and increased.

scholarly journals A Radio Frequency Electric Current Enhances Antibiotic Efficacy against Bacterial Biofilms

2004 ◽  
Vol 48 (12) ◽  
pp. 4662-4664 ◽  
Author(s):  
R. Caubet ◽  
F. Pedarros-Caubet ◽  
M. Chu ◽  
E. Freye ◽  
M. de Belém Rodrigues ◽  
...  
Keyword(s):  
Radio Frequency ◽  
Electric Current ◽  
Direct Current ◽  
Bacterial Biofilms ◽  
Direct Electric Current ◽  
Bioelectric Effect ◽  
Alternating Electric Current ◽  
Antibiotic Efficacy ◽  
Polar Parts ◽  
Biofilm Matrix

ABSTRACT Bacterial biofilms are notably resistant to antibiotic prophylaxis. The concentration of antibiotic necessary to significantly reduce the number of bacteria in the biofilm matrix can be several hundred times the MIC for the same bacteria in a planktonic phase. It has been observed that the addition of a weak continuous direct electric current to the liquid surrounding the biofilm can dramatically increase the efficacy of the antibiotic. This phenomenon, known as the bioelectric effect, has only been partially elucidated, and it is not certain that the electrical parameters are optimal. We confirm here the bioelectric effect for Escherichia coli biofilms treated with gentamicin and with oxytetracycline, and we report a new bioelectric effect with a radio frequency alternating electric current (10 MHz) instead of the usual direct current. None of the proposed explanations (transport of ions within the biofilm, production of additional biocides by electrolysis, etc.) of the direct current bioelectric effect are applicable to the radio frequency bioelectric effect. We suggest that this new phenomenon may be due to a specific action of the radio frequency electromagnetic field upon the polar parts of the molecules forming the biofilm matrix.

Antimicrobial Efficacy of Exposure of Medical Metal Implants to Direct Electric Current

2022 ◽  
Author(s):  
E. N. Ovchinnikov ◽  
N. V. Godovykh ◽  
O. V. Dyuryagina ◽  
M. V. Stogov ◽  
D. N. Ovchinnikov ◽  
...  
Keyword(s):  
Electric Current ◽  
Antimicrobial Efficacy ◽  
Direct Electric Current ◽  
Metal Implants

scholarly journals Investigation of changes in the characteristics of LED matrices of the on-board luminaire during tests in the electrocycling mode.

2021 ◽  
Author(s):  
I.V. Frolov ◽  
◽  
V.A. Sergeev ◽  
A.M. Hodakov ◽  
S.A. Zaytsev ◽  
...  
Keyword(s):  
Leakage Current ◽  
Direct Current ◽  
Coefficient Of Variation ◽  
Convection Heat Transfer ◽  
Voltage Range ◽  
The Matrix ◽  
Operating Current ◽  
In Series ◽  
The Difference ◽  
A Current

The paper presents the results of studies of changes in the characteristics of LED COB matrices of the GW P9LR31.EM - DURIS S 8 type as part of a LED luminaire when tested under the direct current in a continuous mode and in an electrocycling mode. The arrays consist of eight InGaN/GaN LED dies connected in series, coated with a phosphor. Calculation in the Comsol Multiphtsics environment of the temperature field of the luminaire at the rated operating current and free convection heat transfer showed that the maximum overheating of the matrices does not exceed 46 K, and the difference in their temperatures is 2 K. At the same time, the experimental values of the thermal resistances of the matrices of a real lamp vary from 42 to 58 K/W. Before testing, the I-V characteristics of the matrices differ markedly in the level of leakage current in the voltage range from 14 V to 19 V, and the LEDs in the luminaire matrices have a significant spread in the brightness of emission in the microcurrent mode. The degree of this scatter within each matrix was estimated by measuring the luminescence brightness of each die of the matrix and calculating the coefficient of variation γ. It was found that the coefficient of variation of the emission brightness of the COB matrix dies measured at a current of 100 nA strongly correlates with the leakage current. When testing a luminaire under the direct current, the most significant changes in the electrophysical and optical characteristics of COB matrices are observed in the range of microcurrents: the distribution of the emission brightness of the matrix dies at a current of 100 nA becomes more uniform. The greatest changes in matrix characteristics were observed after the first 700 hours of testing, that is, at the running-in stage. At the same time, no correlation was found between the degree of change in the characteristics of the matrices during tests and their thermal resistances.

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