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We have analysed the local earthquakes (2.0 ≤ ML ≤ 5.5) occurred in northeast (NE) India recorded by a temporary seismic network of 10 stations operated by National Geophysical Research Institute (NGRI), Hyderabad to evaluate the relative contributions of scattering loss ($Q_{{\rm sc}}^{ - 1}$) and intrinsic absorption ($Q_{\rm i}^{ - 1}$) to total attenuation ($Q_{\rm t}^{ - 1}$) using the multiple lapse time window analysis assuming multiple isotropic scattering in a medium of uniformly distributed scatterers. The results show that $Q_{\rm i}^{ - 1}$ is greater than $Q_{{\rm sc}}^{ - 1}$ at high frequencies (f > 3 Hz), while the opposite is observed at low frequencies (f < 3 Hz). The observed frequency dependence of $Q_{{\rm sc}}^{ - 1}$ corresponds to the scale length of lithospheric heterogeneity beneath NE India, at least comparable with the wavelength for the lowest frequencies analysed, of about 1 km. The observed $Q_{{\small c}}^{ - 1}$ for the study region obtained with single scattering theory is close to $Q_{\rm i}^{ - 1}$ at high frequencies, in agreement with theoretical prediction for an idealized case of uniform distribution of scatterers. However, a discrepancy exists between the two at low frequencies, which can be explained by a depth-dependent velocity and attenuation structure. High value of $Q_{\rm t}^{ - 1}$ is correlated with the geology and tectonic settings of the region characterized by Himalayan and Burman collision zones with a strong lateral heterogeneity. The $Q_{\rm i}^{ - 1}$ estimates obtained in this study can be used to infer the average temperature of the lower crust with an upper limit estimate of ∼800 °C assuming a lower crustal gabbroic lithology. [ABSTRACT FROM AUTHOR]

Abstract: Details of the research and development work carried out in India using SX for the treatment of the leach/waste solutions and effluents containing base metals are reviewed, focusing on solutions obtained from low-grade or complex ores, secondary resources or industrial wastes. Commercially available organic extractants, such as hydroxyl-oximes, hydroxyl-quinoline, tertiary amines, substituted phosphoric acid and other phosphate based extractants, have been used for the recovery of metals from acidic, alkaline and mixed sulfate–chloride solutions containing copper, nickel, cobalt, zinc and associated metals. The applicability of commercially available tailor-made extractants is described for the purification and enrichment of the metal contents of lean and complex solutions in an Indian context. Research efforts for the separation and recovery of valuable metals by SX are also highlighted. Treatment of solutions for producing metals by crystallization or electrowinning is described. [Copyright &y& Elsevier]

Using as a case study a granulite from the Kerala Khondalite Belt, India, we show that a former anatectic melt can be preserved as tiny (<25 μm) droplets within refractory minerals, in this case garnet. The melt is either fully crystallized as a Qtz-Ab-Kfs-Bt cryptocrystalline aggregate ("nanogranite"), or completely glassy in inclusions <15 μm. Both nanogranite and glassy inclusions have a peraluminous, ultrapotassic granitic composition that, in this case, does not correspond to a "minimum melt" and points to high melting temperatures, in agreement with the ultrahigh-temperature origin of the rock. This discovery indicates that peritectic minerals, growing during incongruent melting reactions, act as hosts for inclusions of anatectic melt, and that in the general case of slow cooling of the crust these inclusions will occur as nanogranite. Exceptionally, in the smallest inclusions, glass may be present due to inhibition of crystallization. Our results extend the frontiers of petrological and geochemical research in crustal melting, as the composition of natural anatectic melts can be directly analyzed rather than assumed. [ABSTRACT FROM AUTHOR]

Abstract: A native feather-degrading keratinophilic fungus, Trichophyton sp. HA-2, was isolated from feather dumping soil in India and screened for extracellular keratinase using keratin-agar medium (chicken feathers as substrate). The fungus was grown in mineral salt medium and keratinase production was tested. The highest keratinase production was observed at pH 8.0 and a temperature of 35°C for a period of 5 weeks. Keratinase secretion was enhanced when cultures were supplemented with a carbon source and keratin source (chicken feathers). This novel keratinase was purified by DEAE-cellulose and sephadex G-100 column chromatography and characterized. The molecular weight of the keratinase was estimated to be 34kDa by SDS-PAGE. The optimum pH and temperature were determined to be 7.8 and 40°C, respectively. This enzyme was completely inhibited by phenylmethylsulfonyl fluoride (PMSF), indicating the presence of serine protease. [Copyright &y& Elsevier]