Wool fabric was dyed with catechu by two different process sequences using various metal sulphates as mordant. The dyeing behaviour has been assessed by measuring K/S values and different fastness properties. The effect of different metal ions have been studied with respect to their influence on colour and fastness properties. The mechanism of mordant interaction with the fibre has been briefly considered.

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Being highly dynamic by nature due to their changing hydrological regime and to the encroachment of urbanization, inductrialization and changing patterns in agriculture, reliable and timely information about the extent, nature, spatial distribution and temporal behaviour of wetlands is a prerequisite for their e ective management. Optical remote sensing data have been used extensively to generate such information. In this study the European Remote Sensing (ERS-1) Synthetic Aperture Radar (SAR) data collected during April 1993 were used to study the temporal behaviour of the coastal wetlands of the Sunderban delta of West Bengal, India. Account was also taken of the Landsat MSS data of 1973. Shrinkage in the wetlands on the periphery of Calcutta due to the encroachment of urbanization and the development of new islands in the active coastal zone have been observed over a period of 20 years.

The graft copolymerization of acrylic acid onto isotactic polypropylene has been investigated. The grafting was carried out using benzoyl peroxide initiator. Grafting is essentially a surface phenomenon and takes place, mostly, in amorphous region of the fiber. Emphasis, therefore, was placed on various pretreatment techniques for swelling of the fiber, viz, pretreatment with toluene and 1,1 0 2,2 0 tetrachloroethane, ultrasound, and photoirradiation. Process parameters, characterization study such as IR spectroscopy, TGA, and DTA, and properties such as tensile properties, melting temperature, dyeability towards basic dyes, and ion exchange properties were investigated. Benzene was found to be the most suitable solvent for initiator as against the acetone. Tenacity was found to be increased with increase in graft yield and reached to maximum at about 5% graft add-on, and then decreased with further increase in graft add-on. Proportionally, a converse effect was reported in the study of elongation to break. Thermal stability of polypropylene was found to be improved because of grafting. The grafted polypropylene also showed satisfactory dyeability toward basic dyes and also exhibits very good ion exchange properties.

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