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Sangita M. Pachkhande Prafull B. Kamble Aditi Mookherjee C. Rajshekhar Nikhil A. Kavathankar 《Journal of the Geological Society of India》2014,83(1):71-75
The benthic foraminifera from the Savitri estuary are being reported for the first time. The faunal analyses reveal the occurrence of mixed assemblage. It is observed that Trochammina inflata is the most dominant species and appears to be the indigenous to mangrove environment. 相似文献
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Venkata Swamy Yerramsetti Nikhil Gauravarapu Navlur Venkanna Rapolu N. S. K. Chitanya Dhulipala Puna Ram Sinha Shailaja Srinavasan Gangagni Rao Anupoju 《洁净——土壤、空气、水》2013,41(3):215-225
In this study, temporal variations of surface ozone (O3) were investigated at tropical urban site of Hyderabad during the year 2009. O3, oxides of nitrogen (NOx = NO + NO2), black carbon (BC), and meteorological parameters were continuously monitored at the established air monitoring station. Results revealed the production of surface O3 from NO2 through photochemical oxidation. Averaged datasets illustrated the variations in ground‐level concentrations of these air pollutants along different time scales. Maximum mean concentrations of O3 (56.75 ppbv) and NOx (8.9 ppbv) were observed in summer. Diurnal‐seasonal changes in surface O3 and NOx concentrations were explicated with complex atmospheric chemistry, boundary layer dynamics, and local meteorology. In addition, nocturnal chemistry of NOx played a decisive role in the formation of O3 during day time. Mean BC mass concentration in winter (10.92 µg m?3) was high during morning hours. Heterogeneous chemistry of BC on O3 destruction and NOx formation was elucidated. Apart from these local observations, long‐range transport of trace gases and BC aerosols were evidenced from air mass back trajectories. Further, statistical modeling was performed to predict O3 using multi‐linear regression method, which resulted in 91% of the overall variance. 相似文献
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Nikhil Padmanabhan Tamás Budavári David J. Schlegel Terry Bridges Jonathan Brinkmann Russell Cannon rew J. Connolly Scott M. Croom István Csabai Michael Drinkwater Daniel J. Eisenstein Paul C. Hewett Jon Loveday Robert C. Nichol Kevin A. Pimbblet Roberto De Propris Donald P. Schneider Ryan Scranton Uro Seljak Tom Shanks István Szapudi Alexander S. Szalay David Wake 《Monthly notices of the Royal Astronomical Society》2005,359(1):237-250
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Tapan K. Saha Nikhil C. Bhoumik Subarna Karmaker Mahmooda G. Ahmed Hideki Ichikawa Yoshinobu Fukumori 《洁净——土壤、空气、水》2011,39(10):984-993
Adsorption of reactive black 5 (RB5) from aqueous solution onto chitosan was investigated in a batch system. The effects of solution pH, initial dye concentration, and temperature were studied. Adsorption data obtained from different batch experiments were modeled using both pseudo first‐ and second‐order kinetic equations. The equilibrium adsorption data were fitted to the Freundlich, Tempkin, and Langmuir isotherms over a dye concentration range of 45–100 µmol/L. The best results were achieved with the pseudo second‐order kinetic and Langmuir isotherm equilibrium models, respectively. The equilibrium adsorption capacity (qe) was increased with increasing the initial dye concentration and solution temperature, and decreasing solution pH. The chitosan flakes for the adsorption of the dye was regenerated efficiently through the alkaline solution and was then reused for dye removal. The activation energy (Ea) of sorption kinetics was estimated to be 13.88 kJ/mol. Thermodynamic parameters such as changes in free energy (ΔG), enthalpy (ΔH), and entropy (ΔS) were evaluated by applying the van't Hoff equation. The thermodynamics of reactive dye adsorption by chitosan indicates its spontaneous and endothermic nature. 相似文献
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Theoretical and Applied Climatology - The vast areal extent of Texas, USA, observes acute variations in extreme precipitation, which result in devastating floods in various regions.... 相似文献
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Groundwater recharge and mounding of water‐table is a complex phenomenon involving time‐ and space‐dependent hydrologic processes. The effect of long‐term groundwater mounding in the aquifer depends on soil, aquifer geometry and the area contributing to recharge. In this paper, a GIS‐based spatio‐temporal algorithm has been developed for the groundwater mound dynamics to estimate the potential rise in the water‐table and groundwater volume balance residual in an unconfined aquifer. The recharge and mound dynamics as predicted using the methodology recommended here were compared with those using the Hantush equation, and the differences were quite significant. The significance of the study is to assess the effectiveness of the basin in terms of its hydrologic and hydraulic properties for sustainable management of groundwater recharge. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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A. J. S. Hamilton Max Tegmark Nikhil Padmanabhan 《Monthly notices of the Royal Astronomical Society》2000,317(1):L23-L27
We present a state-of-the-art linear redshift distortion analysis of the recently published IRAS Point Source Catalog Redshift Survey (PSC z ). The procedure involves linear compression into 4096 KarhunenLoève (signal-to-noise) modes culled from a potential pool of 3105 modes, followed by quadratic compression into three separate power spectra, the galaxygalaxy, galaxyvelocity and velocityvelocity power spectra. Least squares-fitting to the decorrelated power spectra yields a linear redshift distortion parameter 相似文献
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