Theory of Electrolysis at Constant Current in Unstirred Solution. III. Experimental Study of Potential-Time Curves

1954 ◽  
Vol 76 (3) ◽  
pp. 874-878 ◽  
Author(s):  
Paul Delahay ◽  
Calvin C. Mattax
Author(s):  
Vicente D. Munoz-Carpio ◽  
Jerry Mason ◽  
Ismail Celik ◽  
Francisco Elizalde-Blancas ◽  
Alejandro Alatorre-Ordaz

Lead-Acid battery was the earliest secondary battery to be developed. It is the battery that is most widely used in applications ranging from automotive to industrial storage. Nowadays it is often used to store energy from renewable energy sources. There is a growing interest to continue using Lead-Acid batteries in the energy systems due to the recyclability and the manufacturing infrastructure which is already in place. Due to this rising interest, there is also a need to improve the efficiency and extend the life cycle of Lead-Acid batteries. To achieve these objectives, it is necessary to gain a better understanding of the physics taking place within individual batteries. A physics based computational model can be used to simulate the mechanisms of the battery accurately and describe all the processes that are happening inside; including the interactions between the battery elements, based upon the physical processes that the model takes into account. In the present paper, we present a discharge/charge experimental study that has been carried out with small Lead-Acid batteries (with a capacity of 7 Ah). The experiments were performed with a constant current rate of 0.1C [A]1 for two different battery arrangements. An in-house zero dimensional model was developed to perform simulations of Lead-Acid batteries under different operating conditions. A validation analysis of the model was executed to confirm the accuracy of the results obtained by the model compared to the aforementioned experiments. Additional simulations of the battery were carried out under different current rates and geometry modifications in order to study how the performance of the battery may change under these conditions.


2013 ◽  
Vol 712-715 ◽  
pp. 382-386 ◽  
Author(s):  
Peter Michal ◽  
Miroslav Gombár ◽  
Alena Vagaská ◽  
Ján Piteľ ◽  
Ján Kmec

The effects of six factors, affecting during the acid zinc plating process as its technological conditions, on the thickness of the resulting zinc coating has been examined. In order to control the quality of the resulting zinc coating deposited on the surface alloy EN 355 at a constant current density of 5 [Adm-2], the mathematical model predicting the thickness of deposited coating was developed using Design of Experiments (DoE) method. The obtained mathematical model describes the resulting deposited layer of zinc coating in dependence on the factor-level changes and combinations with the reliability of 58.75%.


Author(s):  
D. P. Gardiner ◽  
G. Wang ◽  
M. F. Bardon ◽  
M. LaViolette ◽  
W. D. Allan

It has been demonstrated by previous researchers that an approximate value of the bulk flow velocity through the spark plug gap of a running spark ignition engine may be deduced from the voltage and current wave forms of the spark. The technique has become known as spark anemometry and offers a robust means of velocity sensing for engine combustion chambers and other high temperature environments. This paper describes an experimental study aimed at improving performance of spark anemometry as an engine research tool. Bench tests were conducted using flow provided by a calibrated nozzle apparatus discharging to atmospheric pressure. While earlier studies had relied upon assumptions about the shape of the stretching spark channel to relate the spark voltage to the flow velocity, the actual spark channel shape was documented using high-speed video in the present study. A programmable ignition system was used to generate well-controlled constant current discharges. The spark anemometry apparatus was then tested in a light duty automotive engine. Results from the image analysis of the spark channel shape undertaken in the present study have shown that the spark kernel moves at a velocity of less than that of the freestream gas velocity. A lower velocity threshold exists below, which there is no response from the spark. It is possible to obtain a consistent, nearly linear relationship between the first derivative of the sustaining voltage of a constant current spark and the freestream velocity if the velocity falls within certain limits. The engine tests revealed a great deal of cycle-to-cycle variation in the in-cylinder velocity measurements. Instances where the spark restrikes occur during the cycle must also be recognized in order to avoid false velocity indications.


Author(s):  
D. P. Gardiner ◽  
G. Wang ◽  
M. F. Bardon ◽  
M. LaViolette ◽  
W. D. Allan

It has been demonstrated by previous researchers that an approximate value of the bulk flow velocity through the spark plug gap of a running spark ignition engine may be deduced from the voltage and current waveforms of the spark. The technique has become known as spark anemometry and offers a robust means of velocity sensing for engine combustion chambers and other high temperature environments. This paper describes an experimental study aimed at improving performance of spark anemometry as an engine research tool. Bench tests were conducted using flow provided by a calibrated nozzle apparatus discharging to atmospheric pressure. Whereas earlier studies had relied upon assumptions about the shape of the stretching spark channel to relate the spark voltage to the flow velocity, the actual spark channel shape was documented using high speed video in the present study. A programmable ignition system was used to generate well-controlled constant current discharges. The spark anemometry apparatus was then tested in a light duty automotive engine. Results from the image analysis of the spark channel shape undertaken in the present study have shown that the spark kernel moves at a velocity of less than that of the free stream gas velocity. A lower velocity threshold exists below which there is no response from the spark. It is possible to obtain a consistent, nearly linear relationship between the first derivative of the sustaining voltage of a constant current spark and the free stream velocity if the velocity falls within certain limits. The engine tests revealed a great deal of cycle-to-cycle variation in the in-cylinder velocity measurements. Instances where the spark restrikes occur during the cycle must also be recognized in order to avoid false velocity indications.


Author(s):  
Norio Baba ◽  
Norihiko Ichise ◽  
Syunya Watanabe

The tilted beam illumination method is used to improve the resolution comparing with the axial illumination mode. Using this advantage, a restoration method of several tilted beam images covering the full azimuthal range was proposed by Saxton, and experimentally examined. To make this technique more reliable it seems that some practical problems still remain. In this report the restoration was attempted and the problems were considered. In our study, four problems were pointed out for the experiment of the restoration. (1) Accurate beam tilt adjustment to fit the incident beam to the coma-free axis for the symmetrical beam tilting over the full azimuthal range. (2) Accurate measurements of the optical parameters which are necessary to design the restoration filter. Even if the spherical aberration coefficient Cs is known with accuracy and the axial astigmatism is sufficiently compensated, at least the defocus value must be measured. (3) Accurate alignment of the tilt-azimuth series images.


Author(s):  
P.E. Russell ◽  
I.H. Musselman

Scanning tunneling microscopy (STM) has evolved rapidly in the past few years. Major developments have occurred in instrumentation, theory, and in a wide range of applications. In this paper, an overview of the application of STM and related techniques to polymers will be given, followed by a discussion of current research issues and prospects for future developments. The application of STM to polymers can be conveniently divided into the following subject areas: atomic scale imaging of uncoated polymer structures; topographic imaging and metrology of man-made polymer structures; and modification of polymer structures. Since many polymers are poor electrical conductors and hence unsuitable for use as a tunneling electrode, the related atomic force microscopy (AFM) technique which is capable of imaging both conductors and insulators has also been applied to polymers.The STM is well known for its high resolution capabilities in the x, y and z axes (Å in x andy and sub-Å in z). In addition to high resolution capabilities, the STM technique provides true three dimensional information in the constant current mode. In this mode, the STM tip is held at a fixed tunneling current (and a fixed bias voltage) and hence a fixed height above the sample surface while scanning across the sample surface.


1962 ◽  
Vol 5 (4) ◽  
pp. 387-394 ◽  
Author(s):  
Bruce Quarrington ◽  
Jerome Conway ◽  
Nathan Siegel
Keyword(s):  

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