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31.
This study investigated the removal of two model pharmaceutically active compounds (PhAcs), viz., ibuprofen and triclosan, in lab‐scale engineered floodplain filtration (EFF) system. Biodegradation experiments were performed to acquire knowledge about the degradation of the targeted PhAcs, at an initial concentration of 350 µg/L. Biodegradation results showed that the two compounds were bio‐transformed to >70% after 15 days of incubation. Column tests were performed in a statistically significant manner to determine the adsorptive potential of the suggested filler layer in the EFF (C/C0), by varying the flow rate and initial concentration of the compound. It was observed based on the F and p‐values that the main effects (F = 3163, p < 0.005) were more significant than the interactive effects (F = 9561, p < 0.05) for both ibuprofen and triclosan removal. Besides, by performing the Student's “t” test, it was concluded that the flow rate plays a major role in determining the rapidness of achieving complete breakthrough than the initial concentration of both the compounds. The data obtained from column studies under biotic conditions indicated that the removal mechanism for PhAcs is mainly biotransformation based, and that an EFF system may be effectively used to remove these emerging compounds during ground water recharge for water recycling. 相似文献
32.
String cloud cosmological models are studied using spatially homogeneous and anisotropic Bianchi type VIh metric in the frame work of general relativity. The field equations are solved for massive string cloud in presence of bulk
viscosity. A general linear equation of state of the cosmic string tension density with the proper energy density of the universe
is considered. The physical and kinematical properties of the models have been discussed in detail and the limits of the anisotropic
parameter responsible for different phases of the universe are explored. 相似文献
33.
D. K. Rout P. K. Parida G. Behera 《Journal of the Indian Society of Remote Sensing》2005,33(2):291-295
The breaching of the NALCO Ash-pond in the midnight of December 31, 2000 had caused a serious havoc in 26 villages of the
Angul and the Talcher Tahasils of Angul district in Orissa. The Nandira Jhor, a tributary of the Brahmani river flowing adjacent
to the pond carried ash to the Brahmani river and its effect was noticed up to 50 km downstream of the river. A study was
immediately taken up to assess and evaluate the extent of affected areas using high resolution optical data IRS-ID(PAN) and
IRS-ID LISS III of period January 6, 2001. The cadastral maps covering 14 villages of the Talcher Tahasil and 12 villages
of the Angul Tahasil were scanned and complete mosaic of 26 villages was prepared. The village layer map was superimposed
on the merged data (IRS-ID LISS III+PAN) product at scale 1:8000 and the affected areas were identified village-wise. The
final map was immediately handed over to the NALCO authorities for initiation of relief measures. The landuse/ land cover
map of pre-breaching (IRS-ID LISS III December 12,2000) and post-breaching (IRS-ID LISS III January 6, 2001) periods were
prepared and the spatial extent of different landuse/ land cover class for two dates data were calculated village-wise separately.
It was revealed that most of the agricultural lands, land with or without scrub, fallow areas were fully submerged with water
mixed with ash. It is seen that villages namely Dighi, Gurujanguli, Nuagoan, Khamana of the Talcher Tahasil and the villages
namely Tetoi, Tentolei, Balaramprasad of the Angul Tahasil were seriously affected with high rate of ash deposits. 相似文献
34.
S. K. Behera M.Tech E. R. Rene M.Tech D. V. S. Murthy 《International Journal of Environmental Science and Technology》2007,4(2):247-252
Laboratory scale studies were conducted in an up-flow anoxic bioreactor using synthetic fertilizer wastewater for ascertaining the denitrification efficiency. The performance of the reactor was compared using ethanol and topioca starch as the carbon source. The initial No3-N concentrations (50–250 mg/L) and hydraulic retention time (FTRT, 12–24 h) were varied to evaluate the COD and No3-N removal. The results from this study shows that ethanol gave very good denitrification efficiency (78–98%) compared to topioca starch (68–96%). 相似文献
35.
Hengyi Weng Karumuri Ashok Swadhin K. Behera Suryachandra A. Rao Toshio Yamagata 《Climate Dynamics》2007,29(2-3):113-129
Present work uses 1979–2005 monthly observational data to study the impacts of El Niño Modoki on dry/wet conditions in the Pacific rim during boreal summer. The El Niño Modoki phenomenon is characterized by the anomalously warm central equatorial Pacific flanked by anomalously cool regions in both west and east. Such zonal SST gradients result in anomalous two-cell Walker Circulation over the tropical Pacific, with a wet region in the central Pacific. There are two mid-tropospheric wave trains passing over the extratropical and subtropical North Pacific. They contain a positive phase of a Pacific-Japan pattern in the northwestern Pacific, and a positive phase of a summertime Pacific-North American pattern in the northeastern Pacific/North America region. The western North Pacific summer monsoon is enhanced, while the East Asian summer monsoon is weakened. In the South Pacific, there is a basin-wide low in the mid-latitude with enhanced Australian high and the eastern South Pacific subtropical high. Such an atmospheric circulation pattern favors a dry rim surrounding the wet central tropical Pacific. The El Niño Modoki and its climate impacts are very different from those of El Niño. Possible geographical regions for dry/wet conditions influenced by El Niño Modoki and El Niño are compared. The two phenomena also have very different temporal features. El Niño Modoki has a large decadal background while El Niño is predominated by interannual variability. Mixing-up the two different phenomena may increase the difficulty in understanding their mechanisms, climate impacts, and uncertainty in their predictions. 相似文献
36.
Pulakesh Das Mukunda Dev Behera Nitesh Patidar Bhabagrahi Sahoo Poonam Tripathi Priti Ranjan Behera S K Srivastava Partha Sarathi Roy Praveen Thakur S P Agrawal Y V N Krishnamurthy 《Journal of Earth System Science》2018,127(2):19
As a catchment phenomenon, land use and land cover change (LULCC) has a great role in influencing the hydrological cycle. In this study, decadal LULC maps of 1985, 1995, 2005 and predicted-2025 of the Subarnarekha, Brahmani, Baitarani, Mahanadi and Nagavali River basins of eastern India were analyzed in the framework of the variable infiltration capacity (VIC) macro scale hydrologic model to estimate their relative consequences. The model simulation showed a decrease in ET with 0.0276% during 1985–1995, but a slight increase with 0.0097% during 1995–2005. Conversely, runoff and base flow showed an overall increasing trend with 0.0319 and 0.0041% respectively during 1985–1995. In response to the predicted LULC in 2025, the VIC model simulation estimated reduction of ET with 0.0851% with an increase of runoff by 0.051%. Among the vegetation parameters, leaf area index (LAI) emerged as the most sensitive one to alter the simulated water balance. LULC alterations via deforestation, urbanization, cropland expansions led to reduced canopy cover for interception and transpiration that in turn contributed to overall decrease in ET and increase in runoff and base flow. This study reiterates changes in the hydrology due to LULCC, thereby providing useful inputs for integrated water resources management in the principle of sustained ecology. 相似文献
37.
Shaikh Azhar M. Kumar Satya P. Patel Suresh C. Thakur Satyajeet S. Ravi Subramanian Behera Duryadhan 《Mineralogy and Petrology》2018,112(2):609-624
Distinctly different groundmass mineralogy characterise the hypabyssal facies, Mesoproterozoic diamondiferous P3 and P4 intrusions from the Wajrakarur Kimberlite Field, southern India. P3 is an archetypal kimberlite with macrocrysts of olivine and phlogopite set in a groundmass dominated by phlogopite and monticellite with subordinate amounts of serpentine, spinel, perovskite, apatite, calcite and rare baddeleyite. P4 contains mega- and macrocrysts of olivine set in a groundmass dominated by clinopyroxene and phlogopite with subordinate amounts of serpentine, spinel, perovskite, apatite, and occasional gittinsite, and is mineralogically interpreted as an olivine lamproite. Three distinct populations of olivine, phlogopite and clinopyroxene are recognized based on their microtextural and compositional characteristics. The first population includes glimmerite and phlogopite–clinopyroxene nodules, and Mg-rich olivine macrocrysts (Fo 90–93) which are interpreted to be derived from disaggregated mantle xenoliths. The second population comprises macrocrysts of phlogopite and Fe-rich olivine (Fo 81–89) from P3, megacrysts and macrocrysts of Fe-rich olivine (Fo 85–87) from P4 and a rare olivine–clinopyroxene nodule from P4 which are suggested to have a genetic link with the precursor melt of the respective intrusions. The third population represents clearly magmatic minerals such as euhedral phenocrysts of Fe-rich olivine (Fo 85–90) crystallised at mantle depths, and olivine overgrowth rims formed contemporaneously with groundmass minerals at crustal levels. Close spatial association and contemporaneous emplacement of P3 kimberlite and P4 lamproite is explained by a unifying petrogenetic model which involves the interaction of a silica-poor carbonatite melt with differently metasomatised wall rocks in the lithospheric mantle. It is proposed that the metasomatised wall rock for lamproite contained abundant MARID-type and phlogopite-rich metasomatic veins, while that for kimberlite was relatively refractory in nature.
相似文献38.
Influence of dissolved oxygen concentration and aeration time on nitrite accumulation in partial nitrification process 总被引：1，自引：1，他引：0
X. Guo Ph. D. J. H. Kim Ph.D. S. K. Behera Ph.D. H. S. Park Ph.D. 《International Journal of Environmental Science and Technology》2008,5(4):527-534
This study investigated the influence of dissolved oxygen concentration and aeration time on nitrification and nitrite accumulation in an attempt to optimize the recently developed biological-partial-nitritation process for the treatment of strong nitrogen wastewaters. Investigation of dissolved oxygen concentration on ammonium and nitrite oxidation was carried out in a batch reactor. The dissolved oxygen concentration of 0.5 mg O2/L inhibited both ammonium as well as nitrite oxidation, while increase of dissolved oxygen concentration to ～1 mg O2/L increased the ammonium oxidation rate and was comparable to that at higher dissolved oxygen concentrations. Experiments were carried out in a sequencing batch reactor for more than 100 days to investigate the influence of aeration time on nitrite accumulation. The dissolved oxygen concentration was controlled at ～1.0 mg O2/L (in the range of 0.8–1.5 mg/L) during the aeration stage, and volatile suspended solid was maintained at 2.0 g/L while temperature and pH were 30±1°C and 8.3±0.1, respectively. In a typical cycle, complete nitrification occurred at aeration time longer than 6 h. When the aeration time was reduced to 4 h., ～80 % of partial nitritation was achieved. With a further reduction in aeration time to 3 h., nearly 1:1 nitrite/ammonium ratio was yielded. This result revealed that for the reactor design, aeration time determined by feasibility experiments must be considered based on the nitrogen strength in wastewater and biomass concentration in the reactor with dissolved oxygen concentration of ～1.0 mg O2/L for satisfactory partial nitrification with subsequent processes such as anaerobic ammonium oxidation. 相似文献
39.
Saroja Kumar Barik Satyanarayan Bramha Tapan Kumar Bastia Dibakar Behera Pratap Kumar Mohanty Prasanta Rath 《国际泥沙研究》2019,34(3):251-261
The current study focuses on the vertical profile of different geochemical fractions of phosphorus-loosely bound(Lo–P),aluminium bound(Al–P),iron bound(Fe–P),calcium bound(Ca–P),and organic bound phosphorus(O–P)along with ecological risk assessment of sediment cores from Chilika Lake,eastcoast of India.The percentage contribution of the different fractions to the sedimentary phosphorus in the sediment column of the whole lake are on the order:O–P(33.2%)>Ca–P(20.3%)>Fe–P(18%)>Al–P(6.7%)>Lo–P(0.35%).The Phosphorus Pollution Index(PPI)revealed the contamination of lake sediment with phosphorus.The principal component and cluster analyses highlighted the anthropogenic contribution of phosphorus.The negative loading of Ca–P with Ca points towards its origin from marine shells.The discriminate analysis showed that the variables like Ca–P,bio-available phosphorus(BAP),and pH were able to effectively discriminate the sectors in a significant manner. 相似文献
40.
The present study attempts to delineate different groundwater potential units using remote sensing and geographic information
system (GIS) in Khallikote block of Ganjam disrict, Orissa. Thematic maps of geology, geomorphology, land use and land cover,
drainage density, lineament density, slope and DEM (digital elevation model) were prepared using the Landsat Thematic Mapper
data in 3 spectral bands, band 7 (mid-infrared light), band 4 (near-infrared light), Band 2 (visible green light). Relationship
of each layer to the groundwater regime has been evaluated through detailed analysis of the individual hydrological parameters.
The SMCE (Spatial Multi-Criteria Evaluation) module in ILWIS (Integrated Land and Water Information System) supports the decision-making
process for evaluating the ground water potential zones in the area. The study shows that more than 70% of the block is covered
by medium to excellent category having good ground water potential. 相似文献