Oxygen electrode design criteria and performance characteristics: recessed cathode

1978 ◽  
Vol 45 (1) ◽  
pp. 145-154 ◽  
Author(s):  
G. Schneiderman ◽  
T. K. Goldstick
Keyword(s):  
Measurement Error ◽  
Performance Optimization ◽  
Surrounding Medium ◽  
Three Dimensional ◽  
Concentration Field ◽  
Oxygen Electrode ◽  
Current Sensitivity ◽  
Steady State Operation ◽  
Oxygen Electrodes ◽  
And Performance

A computer simulation of the steady-state operation of recessed (Whalen-type) polarographic oxygen electrodes has been developed to give the design factors important for performance optimization. The simulation makes use of a specially formulated three-dimensional orthogonal coordinate system with the geometry identical to the actual recessed cathode and gives the oxygen concentration field induced by it in the surrounding medium. Equations are presented which allow one to calculate, for any recessed cathode, the current sensitivity, maximum stirring artifact, measurement error, and time constant. Comparisons with analytically obtained expressions for the corresponding quantities for idealized, spherosymmetric cathodes demonstrate the unique aspects of recessed-cathode performance. For commonly used electrodes, a recess length-to-cathode diameter ratio of greater than 10 is found to give a negligible stirring artifact, a negligible measurement error, and a rapid response.

Macroscopic and Microscopic Effects in Diffusion and Reaction in Catalyst Porous Particles

2009 ◽  
Vol 283-286 ◽  
pp. 388-393
Author(s):  
António Martins ◽  
Carlos H. Braga ◽  
Teresa M. Mata
Keyword(s):  
Boundary Conditions ◽  
Network Model ◽  
Three Dimensional ◽  
Concentration Field ◽  
Catalyst Particle ◽  
Network Nodes ◽  
Linear System Of Equations ◽  
Dimensional Network ◽  
Continuous Models ◽  
And Performance

This article presents and discusses a network model to describe and predict the behaviour and performance of catalyst particles. The differences and advantages of this approach when compared to the continuous models currently used in practice are highlighted and critically assessed. The local structure of the catalyst particle is modelled using a three dimensional network model made up of cylindrical pores and nodes of negligible volume. In the pores a homogenous first-order reaction takes place, coupled with the diffusion. For steady state conditions the concentration field can be obtained solving a sparse linear system of equations, obtained by solving the mass balance equations written for the network nodes and using the concentration profile in the network pores. The influence of the boundary conditions and the network sizes was investigated, showing the results in particular that the nature of the boundary conditions can have a profound impact in the predictions of the model.

Electromagnetic performance analysis of the rim electromagnetic direct-driven propeller

2021 ◽  
pp. 095440622199748
Author(s):  
Jian Zhang
Keyword(s):  
Performance Optimization ◽  
Three Dimensional ◽  
Underwater Vehicle ◽  
Test Results ◽  
Three Dimensional Model ◽  
Number Pattern ◽  
And Performance ◽  
Crucial Part ◽  
Electromagnetic Performance ◽  
Computing Models

Propellers are a crucial part to drive underwater vehicles. A rim electromagnetic direct-driven propeller (REDP) had been presented to meet some specific requirements of the underwater vehicle in this paper. It had many advantages compared to classical propellers and could improve the performance of the underwater vehicle. The composition and working mode of REDP were introduced here. In addition, the paper also introduced the working characteristics of REDP and somethings needed to be improved. The energy method was utilized to calculate the distribution of magnetic fields. A three-dimensional model of REDP was built. Then the influence of the propeller’s parameters on performance was analyzed, including the number, pattern, surface radian of the permanent magnet and the stator cogging skew, by finite element computing models. The performances of REDP were tested under several parameters. Some valuable conclusions were obtained according the test results and could provide a reference for the design and performance optimization of REDP utilized on the underwater vehicle.

scholarly journals Improved stability of reversible solid oxide cells with a nickelate-based oxygen electrode

2016 ◽  
Vol 4 (4) ◽  
pp. 1446-1453 ◽  
Author(s):  
M. A. Laguna-Bercero ◽  
H. Monzón ◽  
A. Larrea ◽  
V. M. Orera
Keyword(s):  
High Temperature ◽  
Fuel Cell ◽  
Oxygen Electrode ◽  
Solid Oxide ◽  
Oxygen Electrodes ◽  
Improved Stability ◽  
Electrode Interface ◽  
And Performance ◽  
The Stability ◽  
Fuel Cell Operation

Mixed praseodymium, cerium and gadolinium oxides (PCGO) at the electrolyte–oxygen electrode interface enhance the stability and performance of nickelate based oxygen electrodes in high temperature electrolysis and fuel cell operation modes.

Digitalization system of ancient architecture decoration art based on neural network and image features

2020 ◽  
pp. 1-12
Author(s):  
Wu Xin ◽  
Qiu Daping
Keyword(s):  
Neural Network ◽  
Construction Industry ◽  
Three Dimensional ◽  
Performance Testing ◽  
Image Features ◽  
Three Dimensional Model ◽  
Performance Effect ◽  
Data Process ◽  
And Performance ◽  
Construction Mode

The inheritance and innovation of ancient architecture decoration art is an important way for the development of the construction industry. The data process of traditional ancient architecture decoration art is relatively backward, which leads to the obvious distortion of the digitalization of ancient architecture decoration art. In order to improve the digital effect of ancient architecture decoration art, based on neural network, this paper combines the image features to construct a neural network-based ancient architecture decoration art data system model, and graphically expresses the static construction mode and dynamic construction process of the architecture group. Based on this, three-dimensional model reconstruction and scene simulation experiments of architecture groups are realized. In order to verify the performance effect of the system proposed in this paper, it is verified through simulation and performance testing, and data visualization is performed through statistical methods. The result of the study shows that the digitalization effect of the ancient architecture decoration art proposed in this paper is good.

Sea Urchins and Circuses: The Modernist Natural Histories of Jean Painlevé and Alexander Calder

2018 ◽  
Vol 13 (2) ◽  
pp. 187-211
Author(s):  
Patricia E. Chu
Keyword(s):  
New Media ◽  
Sea Urchins ◽  
Life Sciences ◽  
Three Dimensional ◽  
Machine Age ◽  
Avant Garde ◽  
History Of ◽  
And Performance ◽  
The One ◽  
Natural Historian

The Paris avant-garde milieu from which both Cirque Calder/Calder's Circus and Painlevé’s early films emerged was a cultural intersection of art and the twentieth-century life sciences. In turning to the style of current scientific journals, the Paris surrealists can be understood as engaging the (life) sciences not simply as a provider of normative categories of materiality to be dismissed, but as a companion in apprehending the “reality” of a world beneath the surface just as real as the one visible to the naked eye. I will focus in this essay on two modernist practices in new media in the context of the history of the life sciences: Jean Painlevé’s (1902–1989) science films and Alexander Calder's (1898–1976) work in three-dimensional moving art and performance—the Circus. In analyzing Painlevé’s work, I discuss it as exemplary of a moment when life sciences and avant-garde technical methods and philosophies created each other rather than being classified as separate categories of epistemological work. In moving from Painlevé’s films to Alexander Calder's Circus, Painlevé’s cinematography remains at the forefront; I use his film of one of Calder's performances of the Circus, a collaboration the men had taken two decades to complete. Painlevé’s depiction allows us to see the elements of Calder's work that mark it as akin to Painlevé’s own interest in a modern experimental organicism as central to the so-called machine-age. Calder's work can be understood as similarly developing an avant-garde practice along the line between the bestiary of the natural historian and the bestiary of the modern life scientist.

Electrical Capacitance Volume Tomography (ECVT) for industrial and medical applications-An Overview

2015 ◽  
Vol 11 (1) ◽  
pp. 2897-2908
Author(s):  
Mohammed S.Aljohani
Keyword(s):  
Imaging Technique ◽  
Three Dimensional ◽  
Biological Processes ◽  
Electrical Capacitance ◽  
Image Reconstruction Techniques ◽  
Phase Dynamics ◽  
Non Invasive ◽  
Electrical Capacitance Volume Tomography ◽  
And Performance ◽  
Optimization And Performance

Tomography is a non-invasive, non-intrusive imaging technique allowing the visualization of phase dynamics in industrial and biological processes. This article reviews progress in Electrical Capacitance Volume Tomography (ECVT). ECVT is a direct 3D visualizing technique, unlike three-dimensional imaging, which is based on stacking 2D images to obtain an interpolated 3D image. ECVT has recently matured for real time, non-invasive 3-D monitoring of processes involving materials with strong contrast in dielectric permittivity. In this article, ECVT sensor design, optimization and performance of various sensors seen in literature are summarized. Qualitative Analysis of ECVT image reconstruction techniques has also been presented.

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