An Erda Study on Proton Migration Induced by Electric Potential in SrZrO3,SrCeO3 and BaCeO3 Oxides:Measurements of Proton Transport Number and Proton Diffusivity

1998 ◽  
Vol 513 ◽  
Author(s):  
A. Kunimatsu ◽  
T. Arai ◽  
K. Takahiro ◽  
S. Nagata ◽  
S. Yamaguchi ◽  
...  

ABSTRACTMigration of protons dissolved in acceptor doped SrZrO3, SrCeO3 and BaCeO3 oxides has been examined under an applied electric potential over a range of temperature from 25 to 220°C. Protons which dissolved in these oxides migrated to the cathode, and they were trapped there when the cathode material had a good ability to getter the migrating hydrogen. The amount of hydrogen accumulated in the cathode could be measured by the ERDA method using a highenergy 4He beam. We measured the amount of hydrogen in the cathode while monitoring the dc current passed through the oxide specimen. The proton transport number was determined from the ratio of the number of hydrogen in the cathode to the total numbers of charge through the specimen. The diffusion coefficient of proton was evaluated using the proton transport number and proton concentration in the specimen.

2015 ◽  
Vol 119 (34) ◽  
pp. 19915-19921 ◽  
Author(s):  
E. Mitchell Hopper ◽  
Edith Perret ◽  
Brian J. Ingram ◽  
Hoydoo You ◽  
Kee-Chul Chang ◽  
...  

Author(s):  
Reiyu Chein ◽  
Baogan Chung

In this study, electrokinetic transport in a micro-nanofluidic system is numerically investigated by solving the transient Poisson, Nernst-Planck, and Navier-Stokes equations simultaneously. The system considered is a nanochannel connected with two microchannels at its ends. Under various applied electric potential biases, the effect of concentration polarization on the fluid flow, induced pressure and electric current is examined. By comparing with the Donnan equilibrium condition and electroosmotic flow in microscale dimension, electric body force due to non-zero charge density is the mechanism for producing vortex flow and inducing positive pressure gradient in the anodic side of the system. The diffusive boundary layer thickness is reduced due to the stirring of the generated vortex flow and results in the over-limiting current when the applied electric potential bias is high.


1925 ◽  
Vol 7 (4) ◽  
pp. 461-471 ◽  
Author(s):  
E. J. Lund ◽  
G. A. Logan

1. The experiments demonstrate that when a constant electric potential of sufficient intensity is applied to Noctiluca, the protoplasmic films which represent a part of the visible continuous phase of the cytoplasm and plasma membrane at the surface of the cell, become unstable and break down, thus releasing the acid contents of one of the internal discontinuous phases present in the cytoplasm of Noctiluca. This process which occurs first at anode then at the cathode side of the cell, appears to be a selective deemulsification or coalescence similar to that at the surface of an emulsion having a viscous continuous phase. 2. The experiments demonstrate that Nernst's equation See PDF for Equation which expresses approximately the relation of duration and intensity of a constant electric current to threshold stimulation of striated muscle, applies equally well to the process of anodal coalescence in Noctiluca. 3. Anodal and cathodal coalescence have different thresholds, due to the fact that the semipermeable plasma film at the surface of the cell is asymmetric with respect to the direction of the applied current. Attention is called to the possible relation between this phenomenon and the conditions occurring at the synapse between neurons. 4. The stability of the protoplasmic films in relation to the applied electric potential is greater in young cells than in old cells, or in other words the threshold intensity of the stimulus is higher for young than for old cells. 5. Attention is called to the occurrence in the same cell of different receptor-affector mechanisms having a corresponding difference in intensity threshold when an electric current is acting as a stimulus.


1988 ◽  
Vol 135 ◽  
Author(s):  
Jun Tsuchiya

AbstractIonic migration of cross-linked amorphous Poly (Ethylene Oxide)-LiCF3SO3was investigated by measuring ionic conductivity and diffusion coefficient. Pulsed-Field-Gradient NMR (PFG-NMR) was used for the diffusion measurement. The measurements were carried out at a temperature region between room temperature and 120°C. The PFG-NMR mea-surement shows the two modes of migration of both cation(Li) and anion (CF3 SO3-) for specimens containing plasticizer (CH30(CHeiH20)gH3C). The two modes of migration for anion are present for specimens without the plasticizer. Li+ transport number is found to be less than 0.1 for specimens without the plasticizer. Plasticizer is found to increase the Li+ ion transport number.


Micromachines ◽  
2019 ◽  
Vol 10 (9) ◽  
pp. 585 ◽  
Author(s):  
Krishna ◽  
Alnaimat ◽  
Mathew

: An experimentally validated mathematical model of a microfluidic device with nozzle-shaped electrode configuration for realizing dielectrophoresis based 3D-focusing is presented in the article. Two right-triangle shaped electrodes on the top and bottom surfaces make up the nozzle-shaped electrode configuration. The mathematical model consists of equations describing the motion of microparticles as well as profiles of electric potential, electric field, and fluid flow inside the microchannel. The influence of forces associated with inertia, gravity, drag, virtual mass, dielectrophoresis, and buoyancy are taken into account in the model. The performance of the microfluidic device is quantified in terms of horizontal and vertical focusing parameters. The influence of operating parameters, such as applied electric potential and volumetric flow rate, as well as geometric parameters, such as electrode dimensions and microchannel dimensions, are analyzed using the model. The performance of the microfluidic device enhances with an increase in applied electric potential and reduction in volumetric flow rate. Additionally, the performance of the microfluidic device improves with reduction in microchannel height and increase in microparticle radius while degrading with increase in reduction in electrode length and width. The model is of great benefit as it allows for generating working designs of the proposed microfluidic device with the desired performance metrics.


2009 ◽  
Vol 63 (27) ◽  
pp. 2396-2398 ◽  
Author(s):  
Anping Tang ◽  
Xianyou Wang ◽  
Guorong Xu ◽  
Ronghua Peng ◽  
Huidong Nie

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