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Hydropower generation from the Himalayan rivers in India faces challenge in the form of silt-laden water which can erode the turbine blades and reduce turbine life. To address this issue, polyurethane coatings reinforced with boron carbide (BC) or silicon carbide (SiC) nanoparticles on 16Cr-5Ni martensitic stainless steel substrate were used in the present investigation to improve erosion wear resistance in silt erosion conditions. Slurry erosive wear tests were carried out based on ASTM G-73 protocol at various test conditions of impact velocity, impingement angle, and erodent particle size as well as slurry concentrations as determined by the implementation of Taguchi design of experiments. Analysis of variance studies of erosion rate indicated that nanoparticle content in PU material is the single most important parameter, and interaction of impact velocity and impingement angle was also proved to be significant. The coatings with BC nanoparticles had higher wear resistances than those with SiC nanoparticles due to higher hardness of the former. An interesting finding from the results is that there is an optimum amount of nanoparticles at which mass removal is the minimum. This observation has been explained in terms of surface characteristics of coatings as brought out by a combination of measurements including SEM images as well as roughness measurement. [ABSTRACT FROM AUTHOR]

Bacterial strains having high BPA tolerance were isolated from seawater and sediment samples collected from coastal regions of Chennai, Tamil Nadu, India. Three different bacteria, designated as K-6, K-8, and KU-3, showed the best degradation efficiency of 78 ± 4%, 81 ± 3%, and 74 ± 2%, respectively, at 150 rpm (12 days at 37 °C) in mineral medium supplemented with 1000 ppm BPA. The best degradation was obtained at pH 7.0 and it subsequently decreased with alteration of pH. Sodium glutamate as co-substrate accelerated the degradation efficiency 85 ± 3% (K-8), 83 ± 2% (K6), and 81 ± 3% (KU-3). The bacterial strains K-6, K-8, and KU-3 exhibited degradation rates of 78%, 70%, and 61%, respectively, for 150 rpm (15 days at 37 °C) in the seawater containing BPA (1000 ppm) as a sole carbon and energy source. Residual BPA was analyzed by gas chromatography. These strains were identified as Pseudomonas sp. strain KU1, Pseudomonas sp. strain KU2, and Bacillus sp. strain KU3 by partial 16S rDNA analysis. [ABSTRACT FROM AUTHOR]

The present study was evaluated the trace metals load and antimicrobial effect of three important medicinal plants in southern India namely, Mukia maderaspatana, Kedrostis foetidissima and Cayratia pedata. The phytochemical analysis was tested by using ethanol extract of these plants and the alkaloids, flavonoids, tannins, saponins, terpenoids, steroids and sugars were presented. These plants were challenged against certain pathogens which are obtained from MTCC and NCIM. The antimicrobial effect showed that higher concentration (30 µl) got good effect than lower concentration (15 µl). In trace metal analysis, Cd and Ni was not present (below detectable limit) in all the three plants while Cr, Cu, Fe and Zn was present in the entire sample. [ABSTRACT FROM AUTHOR]

Human population growth, movement, and demand have a substantial impact on land use and land cover dynamics. Thematic maps of land use and land cover (LULC) serve as a reference for scrutinizing, source administration, and forecasting, making it easier to establish plans that balance preservation, competing uses, and growth compressions. This study aims to identify the changeover of land-use changes in the Bhavani basin for the two periods 2005 and 2015 and to forecast and establish potential land-use changes in the years 2025 and 2030 by using QGIS 2.18.24 version MOLUSCE plugin (MLP-ANN) model. The five criteria, such as DEM, slope, aspect, distance from the road, and distance from builtup, are used as spatial variable maps in the processes of learning in MLP-ANN to predict their influences on LULC between 2005 and 2010. It was found that DEM, distance from the road, and distance from the builtup have significant effects. The projected and accurate LULC maps for 2015 indicate a good level of accuracy, with an overall Kappa value of 0.69 and a percentage of the correctness of 76.28%. MLP-ANN is then used to forecast changes in LULC for the years 2025 and 2030, which shows a significant rise in cropland and builtup areas, by 20 km 2 and 10 km 2 , respectively. The findings assist farmers and policymakers in developing optimal land use plans and better management techniques for the long-term development of natural resources., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)