An Analysis of Triode Valve Rectification. Part II

1929 ◽  
Vol 25 (4) ◽  
pp. 482-490
Author(s):  
S. E. A. Landale
Keyword(s):  
Applied Voltage ◽  
Wave Form ◽  
Ordinary Wave ◽  
Applied Potential ◽  
Cambridge University ◽  
Grid Current ◽  
Current Flows ◽  
Grid Potential ◽  
Alternating Voltage ◽  
Peak Value

Generally, when an alternating voltage is applied to a cumulative grid rectifier no grid current flows at mean grid potential. The behaviour of a rectifier working under these conditions is examined. An expression is derived for calculating rectified current for any applied voltage. As this equation is rather cumbersome to apply, a very simply empirical formula is given which is applicable for any value of applied potential whatever.An expression is derived for the power absorbed by the rectifier. It is shown that as the applied voltage increases, the apparent resistance of the rectifier decreases and approaches half the value of the grid leak resistance.Further, it is shown that rectified current depends on the peak value of the applied potential and that it is almost independent of ordinary wave-form variations, even when the applied voltage is small.By slightly modifying the expression for rectified current we find that, in an amplifier, the grid current is a measure of V and, in an oscillator, the grid current is a measure of the output. The only condition is that V > 2b in both cases.In conclusion I wish to express my indebtedness to Professor C. E. Inglis for placing at my disposal the facilities of the Cambridge University Engineering Laboratory, and to Mr E. B. Moullin for the interest he has taken in the work.

THEORETICAL ANALYSIS AND EXPERIMENT OF A NOVEL DEP CHIP WITH 3-D SILICON ELECTRODES

2005 ◽  
Vol 15 (02) ◽  
pp. 231-236 ◽  
Author(s):  
LIMING YU ◽  
FRANCIS E. H. TAY ◽  
GUOLIN XU ◽  
CIPRIAN ILIESCU ◽  
MARIOARA AVRAM
Keyword(s):  
Theoretical Analysis ◽  
Applied Voltage ◽  
Microfluidic Channel ◽  
The Other ◽  
Yeast Cells ◽  
Applied Potential ◽  
Dielectrophoretic Force ◽  
Joule Effect ◽  
Doped Silicon ◽  
Planar Electrodes

This paper presents a novel dielectrophoresis (DEP) device where the DEP electrodes define the channel walls. This is achieved by fabricating microfluidic channel walls from highly doped silicon so that they can also function as DEP electrodes. Compared with planar electrodes, this device increases the exhibited dielectrophoretic force on the particle, therefore decreases the applied potential and reduces the heating of the solution. A DEP device with triangle electrodes has been designed and fabricated. Compared with the other two configurations, semi-circular and square, triangle electrode presents an increased force, which can decrease the applied voltage and reduce the Joule effect. Yeast cells have been used to for testing the performance of the device.

Electrodeposition of CuI Thin Film for Perovskite Solar Cells

2020 ◽  
Vol 979 ◽  
pp. 180-184
Author(s):  
I. Karuppusamy ◽  
K. Ramachandran ◽  
S. Karuppuchamy
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Solar Cells ◽  
Applied Voltage ◽  
Perovskite Solar Cells ◽  
Face Centered Cubic ◽  
Applied Potential ◽  
Cathodic Electrodeposition ◽  
Cubic Structure ◽  
Face Centered

The CuI thin film has been successfully prepared by using cathodic electrodeposition method. The synthesized film was characterized using advanced techniques such as XRD, SEM-EDX and UV measurements. The films are crystallized in face centered cubic structure. The crystallinity is increasing for the applied potential of-0.3 V and the crystallinity deteriorates on increasing the potential above - 0.3 V. It was also observed that the applied voltage plays an important role. Homogeneously distributed triangular faceted morphology was observed from SEM. This is consistent with the result of XRD that electrodeposited CuI thin films grow preferential orientation along the (111) crystal plane.

scholarly journals Air entrapment and its effect on pressure impulses in the slamming of a flat disc on water

2021 ◽  
Vol 928 ◽  
Author(s):  
Utkarsh Jain ◽  
Patricia Vega-Martínez ◽  
Devaraj van der Meer
Keyword(s):  
Liquid Surface ◽  
Ambient Air ◽  
Air Entrapment ◽  
Local Pressure ◽  
Air Trapping ◽  
Cambridge University ◽  
Trapped Air ◽  
Disc Centre ◽  
The Impact ◽  
Peak Value

The presence of ambient air in liquid-slamming events plays a crucial role in influencing the shape of the liquid surface prior to the impact, and the distribution of loads created upon impact. We study the effect of trapped air on impact loads in a simplified geometry, by slamming a horizontal flat disc onto a stationary water bath at a well-controlled velocity. We show how air trapping influences pressure peaks at different radial locations on the disc, how the pressure impulses are affected and how local pressure impulses differ from those obtained from area-integrated (force) impulses at impact. More specifically, we find that the air layer causes a gradual buildup of the load before the peak value is reached, and show that this buildup follows inertial scaling. Further, the same localised pressure impulse at the disc centre is found to be lower than the corresponding (area-integrated) force impulse on the entire disc. While the (area-integrated) force impulses are close to the classical result of Batchelor (An Introduction to Fluid Dynamics, Cambridge University Press, 1967, § 6.10) and Glasheen & McMahon (Phys. Fluids, vol. 8, issue 8, 1996, pp. 2078–2083), the localised pressure impulses at the disc centre, where the trapped air layer is at its thickest, lie closer to the theoretical estimation by Peters et al. (J. Fluid Mech., vol. 724, 2013, pp. 553–580) for an air-cushioned impact.

scholarly journals An Electrochemical System for Forming Periodic Precipitation Bands of Cu-Fe-Based Prussian Blue Analogues

2021 ◽  
Author(s):  
Hisashi Hayashi ◽  
Tomoko Suzuki
Keyword(s):  
Prussian Blue ◽  
Applied Voltage ◽  
Visual Inspection ◽  
Electrochemical System ◽  
Spatiotemporal Evolution ◽  
Agarose Gels ◽  
Periodic Precipitation ◽  
Precipitation Patterns ◽  
Prussian Blue Analogues ◽  
Alternating Voltage

We propose a novel electrochemical system to form precipitation patterns of Cu-Fe-based Prussian blue analogues (Cu-Fe PBA) in agarose gels, using an applied voltage to produce reactant ions. The spatiotemporal evolution, spatial distribution, and crystallite morphologies of the precipitates were investigated by visual inspection, Fe Kα intensity distribution measurements, and optical and scanning electron microscope observations. The precipitation patterns and their evolution depended on the applied voltage. Multicolored periodic precipitation bands were stochastically formed under cyclic alternating voltage (4 V for 1 h and then 1 V for 4 h per cycle). The distances between adjacent bands were randomly distributed (0.30 ± 0.25 mm). The sizes and shapes of the crystallites generated in the gel were position-dependent. Almost cubic but fairly irregular crystallites (0.1–0.8 μm) were formed in the periodic bands, whereas definitely cube-shaped crystallites (1–3 μm) appeared close to the anode. These cube-like reddish-brown crystallites were assigned to Cu-FeII PBA. In some periodic bands, plate-like blue crystallites (assigned to Cu(OH)2) were also present. Future issues for applications of the observed periodic banding were discussed.

A note on the theory of the photo-electric current across a metal semi-conductor contact

1934 ◽  
Vol 30 (1) ◽  
pp. 55-58 ◽  
Author(s):  
R. H. Fowler
Keyword(s):  
Visible Light ◽  
Copper Oxide ◽  
Applied Voltage ◽  
Metal Film ◽  
Reverse Direction ◽  
Similar Group ◽  
Natural Interface ◽  
Current Flows ◽  
A Current

When any metal film is deposited on the surface of a massive copper oxide slab and illuminated with visible light, a current flows in such a direction that the electrons pass from the Cu2O to the metal in greater numbers than from the metal to the Cu2O. This is the reverse direction to the easier flow of electrons under an applied voltage when the contact is allowed to act as a rectifier. This effect is sometimes called the “Vorderwandeffekt” to distinguish it from the similar group of phenomena which occur at the natural interface between massive copper and Cu2O when the surface of the copper has been oxidized in situ (“Hinterwandeffekt”).

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