Utilization of two agrowastes for adsorption and removal of methylene blue: kinetics and isotherm studies.

Fresh water streams contaminated with synthetic dye-containing effluents pose a threat to aquatic and human life either by preventing aquatic photosynthesis or by entering into the food chain. Adsorptive removal of such dyes with potent biosorbents is an important technique to reduce bioaccumulation and biomagnifications of the dyes in human life. We report use of betel nut (BN) husk and banana peel (BP), two most abundant ligno-cellulosic wastes, as efficient adsorbents for the removal of the basic dye methylene blue (MB). The adsorption by BN and BP was consistently high over wide ranges of pH and temperature, suggesting their dye removal potential in diverse conditions. Physico-chemical studies, e.g. scanning electron microscopy and Fourier transform-infrared spectroscopy studies, revealed changes in surface topology and functional moieties of BN and BP post adsorption, implying dye interaction with the biomass surface. The dye adsorption in both cases followed pseudo-second-order kinetics. While adsorption of MB by BN was better fitted with the Temkin isotherm model, adsorption with BP followed both Langmuir and Freundlich isotherm models. Our studies concluded that both adsorbents efficiently remove MB from its aqueous solution with BP proved to be marginally superior to BN.

A review on harmful effects of pan masala.

Pan masala (PM) is a mixture of areca nut with slaked lime, catechu and other flavoring agents. It is widely available and used by all the sections of the Indian society. It is genotoxic as it increases sister chromatin exchange and chromatin aberrations. Among humans, it is a leading cause of oral submucous fibrosis that often progresses to oral cancer. Among experimental animals, it leads to neoplastic lesions in lung, liver and stomach. It is hepatotoxic leading to increased level of enzymes, deranged carbohydrate and lipid metabolism. It is harmful to kidneys and testes leading to increased creatinine and sperm deformities respectively. PM is a very harmful substance affecting almost all organ systems, and there is immediate need for a national policy on complete ban on the production, storage, sale and marketing of PM.

Lagrange time delay estimation for scanning electron microscope image magnification.

Interpolation techniques that are used for image magnification to obtain more useful details of the surface such as morphology and mechanical contrast usually rely on the signal information distributed around edges and areas of sharp changes and these signal information can also be used to predict missing details from the sample image. However, many of these interpolation methods tend to smooth or blur out image details around the edges. In the present study, a Lagrange time delay estimation interpolator method is proposed and this method only requires a small filter order and has no noticeable estimation bias. Comparing results with the original scanning electron microscope magnification and results of various other interpolation methods, the Lagrange time delay estimation interpolator is found to be more efficient, more robust and easier to execute.