Hydrodynamic Study of Bubbles in a Bubble Column Reactor Part I – Image Processing

The study of bubble column reactors has its significance in applications such as multiphase reactors, aerators and in industrial waste-water treatment. Extensive works has been done in studying the hydrodynamics of a single gas bubble flowing through stationary liquid phase. The natural breakup of bubble during its motion has been studied in the past. In the Part I of the present work, hydrodynamics of an air bubble after its artificial splitting using a stainless steel mesh is experimentally studied using image processing and high speed photography. The significance of bubble splitting is that it increases the surface area of contact between stationery and moving fluid which in turn increases the rate of reaction desired during the process. The motion of the bubble is captured during its release and after splitting using High-Speed Camera. The velocity, area and diameter of the bubble before and after splitting are calculated by applying Image processing technique on the high speed photograph. The splitting of the bubble is found to vary with the superficial gaseous velocity. The splitting of bubbles into two bubbles of nearly equal size is considered and its hydrodynamic characteristics are studied.

Coumarins and alkaloids in shoot culture of Ruta graveolens L.

A shoot culture of <em>Ruta graveolens</em> L. (<em>Rutaceae</em>) was maintained in the stationary liquid phase. From the cultured shoots seven compounds were isolated and identified as psoralen, bergapten, xanthotoxin, isopimpinellin (linear furanocoumarins), rutamarin (linear dihydrofuranocoumarin), kokusaginine and skimmianine (furanoquinoline alkaloids) by spectral methods. The compounds are known as secondary metabolites of the intact plant, as well as its cell and tissue cultures.