Fabrication of PVA-Silver nanoparticle composite film for elimination of microbial contaminant from effluent

The effluent contains many harmful microbes which should be eliminated before it is discharged into a water body. Silver nanoparticles (AgNPs) being high-quality significance and have a great impact on this research field as it inhibits microbial proliferation and infection. Therefore, it may use for Bioremediation purposes, our laboratory is fascinated by the production of polymer matrix entrapment silver nanoparticles for in situ bio-remediation purposes. The AgNPs was prepared from sawdust by decoction method. The yellowish solution turns into dark brown colour indicating the formation of AgNPs. A sharp SPR (Surface Plasmon Resonance) band formation in UV-vis spectroscopy scan establishes the formation and stability of silver nanoparticles in an aqueous solution. SEM microphotograph indicated roughly spheroidal structure with (63±3) nm average diameters of newly synthesized AgNp. Polyvinyl alcohol (PVA) is eco-friendly and non-toxic to the environment was chosen for the preparation of polymeric matrix. The non-toxic concentration (1 μg/mL) of AgNp was dispersed into PVA solution followed by cross-linked with maleic acid. PVA- maleic acid is cross-linked by the formation of an ester bond, whereas silver nanoparticles physically entrap into the cross-linked matrix. The silver nanoparticles were released from the matrix nearly after 10 min of swelling of the composite film. In a microbial assay using E. coli agar medium, PVA-AgNp composite film shows the significant killing of microorganisms. Microbial elimination is measured indirectly by pH measurement and dissolved oxygen concentration measurement of the effluent in situ against RO- water, taken as control. The dissolved oxygen concentration from RO water and effluent water was measured on Day “0” followed by treatment and incubation at the BOD chamber. The treatment with PVA-AgNp composite film reduced the BOD Level and increase dissolved oxygen level simultaneously increasing the quality of water

Dust Bath of Bengal Bushlark

34-35The peculiar antics of birds are scientific and always have some purpose. The amusing behavior of Bengal Bushlark having a dust bath shown through pictures

Photo Feature – Yawning of Asian Openbill Stork

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Nature’s Marvels – The Stone-eaters

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Blur adaptation with source and observer methods

Blur adaptation is the improvement of visual and perceptual performance with time following viewing of a blurred target. It is possible to generate blurred images with two different methods – source and observer methods. This study compared blur adaption with source and observer methods for combinations of defocus and higher-order aberrations. Participants adapted to a blurred natural scene for 1 minute and performed a visual acuity task with tumbling Es. Negligible blur adaption was noticed for both source and observer methods. A longer adapting period might be necessary to achieve significant improvement in visual acuity following blur adaptation

Photo Feature – Nasal Salt Secretion of Oriental Pratincole

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Fighting Birds

24-25Most waders fight among themselves for food, nest and breeding territories. Surprisingly, the females become more involved in these fights