Ethyl acrylate (EA), Vinyl imidazole (VI), and their binary mixture have been copolymerized onto rayon in aqueous medium by mutual method using g-radiation. The graft yield has been determined as a function of different reaction parameters such as total dose, concentration of vinyl monomers, and amount of water. Effect of surfactant (1-octane sulfonic acid, sodium salt) has been studied on the percentage of grafting of EA, VI, and (EA þ VI). A plausible mechanism has been suggested to explain the observed behavior of the surfactant on grafting. Water retention and moisture regain of the grafted film was determined at appropriate relative humidity. The graft copolymers have been characterized by IR spectroscopy and scanning electron microscopic methods.

Heavy metals are usually released into water bodies from industrial/domestic effluents such as metal plating industries, mining and tanneries. Adsorption is a fundamental process in the physiochemical treatment of wastewaters because of its low cost. Great efforts have been made to use the economically efficient and unconventional adsorbents to adsorb heavy metals from aqueous solutions, such as plant wastes and agricultural waste. Biochar mixed with chitosan after crosslinking can be casted into membranes, beads and solutions which can be effectively utilized as an adsorbent for metal ion uptake. Keeping these facts into consideration, the present study was undertaken with the objective to determine the effect of various proportions of biochar-modified chitosan membranes on the sorption characteristics of different heavy metals like Cu, Pb, As and Cd along with comparison of sorption characteristics between industrial waste water samples containing multi-metals and standard synthetic stock solution containing a particular metal. It is apparent from the results that the bioadsorbent prepared from biochar and chitosan are low-cost efficacious resource due to its easy availability. It is also eco-friendly material for making adsorbent for abstraction of heavy metals from aqueous solution. This adsorbent can be best utilized for adsorption of heavy metals.

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The environment sensitivity of organic semiconductors may change their molecular structure and hence optical properties. Exploiting this concept, experiments were performed on a green light emitting material bis(8-hydroxy quinoline)Zinc, (Znq 2 ) used in organic light emitting diodes (OLEDs). Thin films were deposited at varying deposition parameters, and their properties were compared. We investigated that as deposited films have a significant component of Znq 2 tetramer out of two known forms, that is, dihydrate and anhydrous tetramer (Znq 2 ) 4 , the films deposited at lower deposition rates have higher anhydrous content. The degradation of thin film is shown, that changes the optical properties of film from green emission to blue which may be due to water adsorption and crystallization.

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