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Superhydrophobic surfaces have been shown to produce significant drag reduction for both laminar and turbulent flows of water through large-and small-scale channels. In this paper, a series of experiments were performed which investigated the effect of superhydrophobic-induced slip on the flow past a circular cylinder. In these experiments, circular cylinders were coated with a series of superhydrophobic surfaces fabricated from polydimethylsiloxane with well-defined micron-sized patterns of surface roughness. The presence of the superhydrophobic surface was found to have a significant effect on the vortex shedding dynamics in the wake of the circular cylinder. When compared to a smooth, no-slip cylinder, cylinders coated with superhydrophobic surfaces were found to delay the onset of vortex shedding and increase the length of the recirculation region in the wake of the cylinder. For superhydrophobic surfaces with ridges aligned in the flow direction, the separation point was found to move further upstream towards the front stagnation point of the cylinder and the vortex shedding frequency was found to increase. For superhydrophobic surfaces with ridges running normal to the flow direction, the separation point and shedding frequency trends were reversed. Thus, in this paper we demonstrate that vortex shedding dynamics is very sensitive to changes of feature spacing, size and orientation along superhydrophobic surfaces.

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Granulation is an important unit process in the production of pharmaceutical dosage forms like tablets, capsules and other dosage forms. Granulation process increases flow, compressibility and content uniformity of the powders. It inhibits the separation of blend components and reduces excessive amount of fine particles. This process helps to achieve improved yields with less tablet manufacturing defects. Particle size of granules depends on the quantity and feeding rate of the granulating liquid. Selecting a method of granulation requires comprehensive study of each ingredient in the formula, the combination of ingredients and their compatibility with each other is checked after, which appropriate granulation process can be applied. The recent technologies used for granulation include steam granulation, moisture activated dry granulation (MADG), moist granulation technique (MGT), extrusion-spheronization granulation, fluidized bed granulation, thermal adhesion granulation process (TAGP) and foam granulation etc. have their own advantages and overcome the disadvantages of conventional granulation process such as dust generation or deteriorating effect of heat as drying step. The objective of present work is to focus on the novel granulation technologies.

Advanced node (sub 2Xnm) chip manufacturing employs new fabrication techniques as well as materials. This work is focused on the Middle of Line (MoL) contact cleaning. An advanced cleaning process is developed based on the electrochemical compatibility and interactions between the chosen chemistry and exposed layers as well as contaminants to be removed. The cleaning efficacy in the trenches is verified by measuring contact resistance as well as particle/flake inspections. Tungsten integrity is verified with bright field microscopy and damage to inter layer dielectrics is monitored by measuring trench and contact critical dimensions. Other structural interactions were studied with TEM imaging. The new cleaning process yielded substantially higher number of functional die as compared to POR (Process of Record).