Current density and duration

As shown in the previous section, localized porous-type anodization and selective etching of A1 can be used for the fabrication of complex microstructures composed from freestanding porous AI2O3. As an example, Fig. 16a and b demonstrates SEM and optical images of microstructured porous AI2O3 substrates, which are utilized for sensor applications (Fig. 16c, d). The lateral dimensions of freestanding ceramic substrates were controlled by the mask design and process conditions. The thickness was controlled by the current density and duration of anodization (2 min anodization... 

Effect of cathodic current density and duration of electrolysis... 

Studies of the effect of the cathodic current density and duration of electrolysis and choice of parameters of the reverse deposition mode were carried out for Na2WO4 - 5 mol% NaP03 and Na2WO4 - 5 mol% Na2S207 electrolytes. Adhesive solid pore-free coatings from electrolytes of the above compositions were obtained at temperatures of 923-1173 K and current densities of 0.03-0.25 AJcrr . 

Dependencies of the /I-NiH phase volume fraction on the nature and concentration of the promotor, changing current density and changing duration were presented and the phenomena observed were explained with the assumption that NiAs-type compounds take part in the formation of nickel hydride. 

Current density was calculated from the current applied and the surface contact area of the iontophoretic probe, if mentioned in this chapter. It is clear from this summary that the two major parameters influencing drug penetration are the current density and iontophoretic duration. Ocular iontophoresis can be delivered by two approaches transcorneal and trans-scleral iontophoresis. 

The slowness of the electrode processes when a stronger current flows through the electrolyzer results in an increase of the back electromotive force Ev, above its theoretical value (i. e. above the EMF of the corresponding galvanic cell). In such an instance Ohm s law (see formula VII-1) will still be valid but the value Ev will no longer be constant but will increase in proportion to the current density and will also depend on the duration of the electrolysis. 

For the same material, by varying the composition of the electrolyte, the current density, and the duration of etching, it is possible to obtain three different types of etching. 

Gyory, J.R. Phipps, J.B. Effect of current density and current duration on the membrane resistance of skin. In Transdermal Administration, A Case Study, Iontophoresis, APGI/CRS European Symposium, Couvreur, P., Duchene, D., Green, P., Junginger, H.E., Eds. 3-4 March 1997 Paris, France Editions de Sante Paris, 1997 262-265. 

Standard commercial p- and n-type 0.5-40 Q cm Cz Si wafers were subjected to H He or Ar ion-beam treatments. The current density and ion energy were equal to 0.15mA/cm and 300 eV, respectively. The treatment duration was 30 min at a temperature ranging from 25 to 350 °C. 

It should be noted that the anodization constant ka for multi-layer compositions differs from that for a single tantalum film. This is because the anodization voltage for the Ta film on a dielectric substrate is 1.5 to 2 times higher than that in the case of A1 bottom layer. Relationships between current density, anodization duration and forming voltage at a constant scanning rate of voltage have been obtained. 

Ash Incinerator bottom ash Pb, Cu, Zn, Cd Polluted Comparative experiments by different current density and process duration Traina, Morselli, and Adorno (2007)... 

When on-time duration of pulse and intervals between the pulses are properly matched to achieve required current density and lEG is swept clean during the current intervals, than this will result in more efficient regular EMM process. The pulse-off time should be long enough to ensure a complete flushing of the electrolyte out of the narrow end gap. The current efficiency is much more dependent on the current density when pulsed voltage is used than the use of continuous voltage. With the... 

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