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Kumar N.,Wadia Institute of Himalayan Geology | Arora B.R.,Uttarakhand State Council for Science and Technology | Mukhopadhyay S.,Indian Institute of Technology Roorkee | Yadav D.K.,Wadia Institute of Himalayan Geology
Journal of Asian Earth Sciences | Year: 2013

To investigate subsurface structure and seismogenic layers, 3D velocity inversion was carried out in the source zone of 1905 Kangra earthquake (M8.0) in the northwestern Himalaya. P-wave and S-wave phase data of 159 earthquakes recorded by a network of 21 stations were used for this purpose. Inverted velocity tomograms up to a depth range of 18km show significant variations of 14% in Vp and Vs and 6% in the Vp/Vs across the major tectonic zones in the region. Synthesis of seismicity pattern, velocity structure, distinctive focal mechanisms coupled with nature of stress distribution allows mapping of three different source regions that control regional seismotectonics. Accumulating strains are partly consumed by sliding of Chamba Nappe to the southwest through reverse-fault movements along Chamba/Panjal/Main Boundary Thrusts. This coupled with normal-fault type displacements along Chenab Normal Fault in the north account for low magnitude widespread seismicity in upper 8-10km of the crust. At intermediate depths from 8 to 15km, adjusting to residual compressive stresses, the detachment or lower end of the MBT slips to produce thrust dominated seismicity. Nucleation of secondary stresses in local NE-SW oriented structure interacts in complex manner with regional stresses to generate normal type earthquakes below the plane of detachment and therefore three seismic regimes at different depths produce intense seismicity in a block of 30×30km2 centered NE to the epicenter of Kangra earthquake. © 2012 Elsevier Ltd. Source

Seth R.,P.A. College | Mohan M.,P.A. College | Singh P.,P.A. College | Haider S.Z.,Center for Aromatic Plants | And 4 more authors.
Asian Pacific Journal of Tropical Biomedicine | Year: 2012

Objective: The purpose of this study was to evaluate the essential oil composition as well as antibacterial activities of essential oil and leaves extracts of Lantana camara against five bacterial strains. Methods: Essential oil was obtained by hydro-distillation from the leaves and analyzed by GC and GC-MS. The antibacterial activities of essential oil and the leaves extracts were tested by using disk diffusion method against five bacterial strains. Results: Thirty seven compounds were identified representing 98.11% of the total oil, of which trans-caryophyllene (13.95%), bicyclogermacrene (9.77%), ±-curcumene (8.57%), sabinene (8.28%), (E)-citral (6.90%), 1,8 cineole (5.06%), ±-pinene (4.03%), -terpinene (3.83%) and germacrene D (3.13%) were detected as major components. In respect to the antibacterial activities, essential oil showed the high degree of sensitivity against Micrococcus luteus, Escherichia coli, Staphylococcus aureus and Bacillus cereus except Pseudomonas aeruginosa while extracts of leaves obtained through petroleum ether, benzene, methanol and water exhibited good to moderate antimicrobial activity against all tested bacterial strains. Conclusions: The present study suggested that M. luteus showed best zone of inhibition for the essential oil as well as aqueous extract among all the tested bacterial strains. The most active extract can be subjected to isolation of the therapeutic antimicrobials to carry out further pharmacological evaluation. © 2012 Asian Pacific Tropical Biomedical Magazine. Source

Mishra A.,Uttarakhand State Council for Science and Technology | Sharma S.D.,Forest Research Institute
Soil Use and Management | Year: 2010

Tree plantation is a proven strategy to improve the salt-affected soils. However, the efficiency of trees to reclaim the soil varies from species to species. This study was therefore, carried out with the objective of assessing the efficiency of 3-yr old plantations of Prosopis juliflora (Swartz) D.C. (Mesquite), Eucalyptus tereticornis Sm. (Forest Red Gum) and Dalbergia sissoo Roxb. Ex. D.C. (Indian Rosewood) to improve the sodic soil characteristics in Sultanpur districts of Uttar Pradesh, India (26°10'-26°23'N, 81°50'-82°5'E). Soil samples collected from six depths; 0.0-0.1, 0.1-0.3, 0.3-0.6, 0.6-0.9, 0.9-1.2 and 1.2-1.5-m below the surface, were analysed for chemical and physical properties by following standard methods. The infiltration rate (IR) was determined by double concentric infiltrometer and the permeability by constant head permeameter. The trees were measured for their girth at breast height (at 1.33-m from ground) and crown area within a 100-×-100-m sector at each of the sites selected. There were decreases in soil pH (from 10.06 to 9.64) and exchangeable sodium percentage (from 70.6 to 26.9) at the P. juliflora plantation relative to the E. tereticornis and D. sissoo plantations. The organic carbon and nitrogen content increased from 2.0 and 0.18-g/kg to 3.9 and 0.45-g/kg under P. juliflora at the surface (0.0-0.1-m) layer. There was also more exchangeable Ca 2+, Mg 2+and K + at exchange sites and a reduction in exchangeable Na + 3-yr after establishing the plantations. There was a significant decrease in surface soil (0.1-m) bulk density from 1.66 to 1.37 (t/m 3) but an increase in porosity from 41.2 to 46.3% and water holding capacity from 4.3 to 4.8-g/kg. The IR and soil permeability also increased after 3-yr of tree growth. Prosopis juliflora proved more effective than E. tereticornis and D. sissoo in its ability to enrich a sodic soil with organic matter and establishing better soil-water characteristics. © 2010 The Authors. Journal compilation © 2010 British Society of Soil Science. Source

Singh K.P.,University of Agriculture and Technology | Dobhal R.,Uttarakhand State Council for Science and Technology | Prajapati R.K.,Dj College | Kumar S.,University of Agriculture and Technology | And 2 more authors.
Desalination and Water Treatment | Year: 2010

Molecular imprinting technique is used for preparing molecularly imprinted polymer (MIP) membranes of desired recognition site, selectivity and porosity. The novelty of present work is to use a new approach for preparing imprinted monolith membrane, to study the effect of membrane porosity generated due to molecular imprinting on irreversible thermodynamical characteristics like membrane potential, ion transport, fixed charge density and permselectivity. It seems significant in developing membranes of desired selectivity and porosity for the removal and recognition of templates molecules. MIPs of potent herbicides isoproturon and 2,4-d were prepared by radical polymerization using methyl methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA) as functional monomer and cross linking agent. The polymer synthesis took place on a microporous support, which form hydrogen, covalent and ionic bonds with templates in order to form MIP membranes. The significance of this work is to discuss transport study of MIP membranes after creation of molecular recognition sites within the coated MIP. The MIP membranes were studied using theory of irreversible thermodynamics and by evaluating contact angle measurement, surface energy, ion transport study, perms electivity and fixed charge density of the membranes. © 2010 Desalination Publications. All rights reserved. Source

Nautiyal P.,Hemwati Nandan Bahuguna Garhwal University | Nautiyal R.,P.A. College | Semwal V.P.,P.A. College | Mishra A.S.,Hemwati Nandan Bahuguna Garhwal University | And 4 more authors.
Aquatic Ecosystem Health and Management | Year: 2013

This is the pioneering attempt to study the spatial patterns in structure of lotic ecosystems that form the Ganga River system in the Himalaya. The diversity of source (glacier-fed [GF], snow-fed [SN] and spring-fed [SF]) and stream-size (both interrelated) across the altitudinal panorama, create numerous habitats that contribute to structural diversity. The spatial patterns in richness, density and taxonomic composition and distribution of benthic diatoms are less affected by source compared with macro-invertebrates but shows strong influence on the distribution of fish fauna that are poikiliotherms, because a glacier-fed river carries ice-cold water (usually <20°C) in contrast to normal waters in spring-fed system (22°C near snowline, 32°C in foothills). The abundance patterns of biota of lower organisation grade (diatoms, macro-invertebrates) do not differ sharply even across distant river basins as they are more influenced by proximate factors; thus the sub-basins of the Alaknanda resemble more by virtue of one basin and there is notable resemblance between distant SF Bemunda (lower Ganga basin) and SF Gomti (East Rāmgangā basin) and even the farthest Yamuna and Rāmgangā. Fish are more sensitive to temperature and current velocities that are related to altitude and hence longitudinal rather than the spatial gradients in the mountains. The lotic ecosystem of Doon Valley harbour rich and diverse diatom flora, macroinvertebrate fauna and ichthyofauna. The examination of trophic, saprobic and ecological status shows that organic pollution, degradation and anthropogenic eutrophication are non-existent in the Lesser Himalayan rivers and streams, but the fragile Doon Valley is under severe anthropogenic stress. This and habitats fragmented by hydropower projects in the major rivers has threatened the iconic game fish Himalayan mahseer in the Ganga. © 2013 Copyright Taylor and Francis Group, LLC. Source

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