Informatics Publishing Limited

T. Mukherjee ¹, S. Chatterjee Halder ¹, M. Das ²

Affiliations
1 Scottish Church College, 1&3 Urquhart Square, Kolkata-700006, IN
2 Dept. of Chemical Engineering, University of Calcutta, 92, A.P.C Road, Kolkata-700009, IN

Abstract

The dyes present in textile effluent impart persistent color to the receiving streams and interfere with photosynthesis of the phytoplankton and ecosystem. The triphenylmethane dye malachite green is highly soluble in water and has long been used in the aquaculture industry as a fungicide, parasiticide, and disinfectant. Malachite green is highly toxic to mammalian cells at concentrations as low as 0.1 mg/ml. It also enhances liver tumor formation in rats and causes reproductive abnormalities in rabbits and fish. A bacterial species namely Enterobacter asburiae XJUHX-4TM was isolated from dye contaminating site of a small scale dyeing industry, situated at Habra and was found to show high decolorizing activity against Malachite Green. Decolorization of Malachite was studied by the organism. The organism was utilized in its live form, immobilized form and heat killed-dry form. The organism was found to be most active with respect to decolorization in its live form. The live organism was found to be most promising decolorizer of the dye followed by its immobilized form and dry form. From the experiments conducted it was concluded that the organism is a potent decolorizer of the dye Malachite Green which can be utilized in the treatment of industrial effluent in subsequent studies.

Full Text

     

T. Mukherjee ¹, A. De ¹

Affiliations
1 Mechanical Engineering Department, Indian Institute of Technology Bombay, Mumbai – 400076, IN

Abstract

Laser-arc hybrid welding process employs a laser beam and a welding arc concurrently for the joining of thick plates at high welding speeds. Systematic quantitative studies to understand the role of welding conditions on the rate of heat input and weld pool profile are important but rarely reported for hybrid welding process. The current work presents a three-dimensional heat transfer analysis of hybrid welding process using finite element method. The computed results are validated using experimentally measured results that are reported in the independent literature. The model is used further to examine the effect of welding speed, laser and arc power, and the separation distance between laser beam and welding arc on the weld pool profile. The computed results show that the weld width will reduce with increase in welding speed and the separation distance while the penetration increases with the laser power.

Keywords

Laser-Arc Hybrid Welding, Numerical Model, Heat Transfer Analysis, Weld Pool Profile.

Full Text