Eco-friendly green synthesis of silver nanoparticles (AgNPs) was carried out using leaves extracts of plant Murraya koenigii (curry leaves) and 1 mM silver nitrate solution. During this synthesis the leaf extract works as a reducing agent. The characterization of silver nanoparticles was carried out using UV-visible spectra, scanning electron microscopy and FTIR. The characteristic surface plasmon resonance (SPR) absorption peak was found at 340 nm in UV-visible spectra confirms the formation of silver nanoparticles. The morphological study from SEM images gave an idea about the formation of asymmetrical spherical shape silver nanoparticles which are rested on the leaves extract residue. FTIR spectrum clearly suggested the green synthesis of silver nanoparticles initiated by the leaves extract. This green synthesis method is quite fast, easy to perform and does not involve the use of any harmful and costly chemicals.

Spherical Hydrogels are having the tendency to absorb the large amount of water. This results in swelling of the hydrogels that leads to the increase in mass and volume of hydrogels. In the present work this change in the mass and volume of spherical hydrogels at different time interval has been studied. The different swelling related parameters like mass swelling ratio (MSR), equilibrium swelling ratio (ESR), swelling constant (K) which is the characteristic of polymer network of hydrogel bead, diffusional exponent (n) characterizing the mechanism of diffusion of the solvent into the network ,equilibrium water content (EWC), diffusion coefficient of water (D) , number of absorbing sites per unit mass of dry hydrogel (ρ M) and number of absorbing sites per unit volume of dry hydrogel (ρ N) were determined for four different colored (Red, Blue, Orange and Green) spherical hydrogels. The linear relationship of log () is observed with log (t) and also between change in volume and change in mass of hydrogel. The water intake and volume of hydrogel increases with time initially and later there is no appreciable change in water intake and volume due to maximum water absorption i.e. equilibrium swelling of hydrogels.

Fine powdered activated charcoal was prepared from Wood Apple fruit shell. Carbonization was done at 300 0 C and 500 0 C for two hour and allowed to cool at room temperature. Chemical activation was achieved by impregnating the prepared charcoal with activating reagent 1N ZnCl 2 and heated to 300 0 C and 500 0 C temperature respectively for one hour. Characteristics of the activated carbon were determined using standard methods given by AWWA, CEFIC and also by scanning electron microscopy SEM. A significant difference in the properties of p H , Conductance, Ash content, moisture, Methylene blue value, Iodine value and calorific value were observed on the activated carbons

In the present paper we have studied the dye removal efficiency for Congo red and Methylene blue dye from the aqueous solution by the phenomenon of adsorption. The low cost agricultural waste Pineapple Peel acid activated carbon (PPAC) prepared at three different temperatures 300 0 C, 400 0 C, 500 0 C were used in the present study. Batch experiments were carried out to determine the effect of various parameters such as different initial concentration of dye, Adsorbent dose and Contact time on the dye removal efficiency of activated carbons from the aqueous solution. The experimental results indicate that percentage dye removal efficiency was the highest for PPAC300 and the lowest in case of PPAC500 with respect to the studied parameters. The PPAC300 activated carbon is more suitable for the removal of synthetic dyes from industrial effluents.