The microscale trickle bed reactor can be used for testing commercial size catalyst, if its inherent limitations, such as channeling, wall effect, and backmixing, are overcome by diluting the catalyst bed with a nonporous inert particles of suitable size. The effect of diluent size on the performance of a microscale trickle bed reactor, catalyst bed height, as well as on operating liquid holdup at different liquid hourly space velocities, has been studied in the present investigation. The proper size of diluent, which may be used for testing as low as 5 mL of commercial catalyst in a microreactor, has been identified experimentally. The results on the hydrodesulfurization of atmospheric gas oil obtained in the microreactor, using the suitable size of diluent were compared with the data generated in a bench scale unit. The activation energy calculated from both microreactor and bench-scale reactor rate data was 21 and 25 kcal/mol, respectively.

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The biggest challenge that the neuromorphic community faces today is to build systems that can be considered truly cognitive. Adaptation and self-organization are the two basic principles that underlie any cognitive function that the brain performs. If we can replicate this behavior in hardware, we move a step closer to our goal of having cognitive neuromorphic systems. Adaptive feature selectivity is a mechanism by which nature optimizes resources so as to have greater acuity for more abundant features. Developing neuromorphic feature maps can help design generic machines that can emulate this adaptive behavior. Most neuromorphic models that have attempted to build self-organizing systems, follow the approach of modeling abstract theoretical frameworks in hardware. While this is good from a modeling and analysis perspective, it may not lead to the most efficient hardware. On the other hand, exploiting hardware dynamics to build adaptive systems rather than forcing the hardware to behave like mathematical equations, seems to be a more robust methodology when it comes to developing actual hardware for real world applications. In this paper we use a novel time-staggered Winner Take All circuit, that exploits the adaptation dynamics of floating gate transistors, to model an adaptive cortical cell that demonstrates Orientation Selectivity, a well-known biological phenomenon observed in the visual cortex. The cell performs competitive learning, refining its weights in response to input patterns resembling different oriented bars, becoming selective to a particular oriented pattern. Different analysis performed on the cell such as orientation tuning, application of abnormal inputs, response to spatial frequency and periodic patterns reveal close similarity between our cell and its biological counterpart. Embedded in a RC grid, these cells interact diffusively exhibiting cluster formation, making way for adaptively building orientation selective maps in silicon.