Relationships of surface ozone with its precursors,particulate matter and meteorology over Delhi     

Sharma  Ashima  Mandal  T. K.  Sharma  S. K.  Shukla  D. K.  Singh  S. 《Journal of Atmospheric Chemistry》2017,74(4):451-474

Journal of Atmospheric Chemistry - The paper presents the temporal variations of surface ozone (O3) and its precursors (oxides of nitrogen (NOX), carbon monoxide (CO), methane (CH4) and non-methane...  相似文献   

<Emphasis Type="Italic">Holigarna</Emphasis> (Anacardiaceae) from the early Eocene of Western India and its palaeogeographical and palaeoclimatological significance     

Anumeha Shukla  Rakesh Chandra Mehrotra 《Journal of the Geological Society of India》2016,87(5):520-524

Thick lignite deposits on the western margin of India were preserved on account of thick vegetation which got buried underneath due to tectonic activities that occurred in northwestern part of India during the early Palaeogene. Study of the fossil flora preserved in these beds is important to deduce the palaeoclimate of the region. Therefore, a field work was undertaken to collect plant fossils from the Tarkeshwar lignite mine, Surat district, Gujarat (western India) which is still unexplored as far as the plant mega-remains are concerned. A fossil wood is systematically described from the Cambay Shale Formation of the mine considered to be of early Eocene in age. It shows close affinities with Holigarna (Anacardiaceae), particularly with H. beddomei and H. grahamii. This genus is evergreen in nature and grows in the Indo-Malayan region, while both the modern analogues of the fossil are endemic to semi-evergreen to evergreen forests ofWestern Ghats, south India, located at the equator. This not only confirms the palaeolatitudinal position of the Indian subcontinent at the equator during the early Palaeogene, but also indicates the presence of equatorial rain forest in the Indian subcontinent during the period. Based on the timetree, Sapindales started to diverge in the early Palaeocene (62–57 Ma) as its oldest fossil is from the K-Pg boundary. Discovery of the present anacardiaceous fossil (belonging to Sapindales) from the early Eocene strengthens the above phylogenetic view.  相似文献   

Kinematic vorticity analysis along the Karakoram Shear Zone,Pangong Mountains,Karakoram: Implications for the India–Asia tectonics     

Priyom Roy  A. K. Jain  Sandeep Singh 《Journal of the Geological Society of India》2016,87(3):249-260

The Karakoram Shear Zone (KSZ) is a northwest-southeast trending dextral ductile shear zone that has mylonitized the Tangste and Darbuk granitoids of the southern margin of the Asian plate. Kinematic vorticity (W_k) has been estimated in 6 mylonitized Tangste granite samples, using Porphyroclast Hyperbolic Distribution (PHD) and Shear Band (SB) Analyses methods on well-developed quartz and feldspar porphyroclasts, and synthetic and antithetic shear bands respectively to visualize the overall deformation of the KSZ. The PHD and SB analyses yield W_k values ranging from W_k=0.29 to 0.43 and 0.45 to 0.93, respectively, thus indicating distinct pure and simple shear dominant regimes during different stages of the evolution of the KSZ. Strain has essentially been pure shear when southern edge of the Asian plate was initially juxtaposed against the Indian plate around 70 Ma, and changed to simple shear, possibly during the reactivation of this shear zone during 21-13 Ma to produce the shear bands.  相似文献   

Discovery of <Emphasis Type="Italic">Elephas</Emphasis> cf. <Emphasis Type="Italic">namadicus</Emphasis> from the late Pleistocene strata of Marginal Ganga Plain     

Rupa Ghosh  R. K. Sehgal  Pradeep Srivastava  U. K. Shukla  A. C. Nanda  D. S. Singh 《Journal of the Geological Society of India》2016,88(5):559-568

We describe an elephant skull recovered from a cliff section of Dhasan river of Marginal Ganga Plain. The dental morphology and cranial features of the skull have been compared with the known species of Elephas from the Indian subcontinent. Although it shows very near resemblance to Elephas namadicus, but being an isolated specimen its specific identity cannot be proclaimed with certainty. As such, the specimen is provisionally referred as E. cf. namadicus. The Optically Stimulated Luminescence ages place this find at ~56 ka BP. This is the first chronologically well constrained report of E. cf. namadicus from the Ganga Plain.  相似文献   

Adsorptive removal of reactive dyes from aqueous solution using activated carbon synthesized from waste biomass materials     

P. V. Thitame  S. R. Shukla 《International Journal of Environmental Science and Technology》2016,13(2):561-570

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Adsorptive removal of cobalt ions on raw and alkali-treated lemon peels     

S. A. Singh  S. R. Shukla 《International Journal of Environmental Science and Technology》2016,13(1):165-178

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Hydrochemistry of hot springs in geothermal fields of central,northern, and northeastern Taiwan: implication on occurrence and enrichment of arsenic     

Jiin-Shuh Jean  Libing Liao  Sandeep Kar  Chia-Chuan Liu  Zhaohui Li 《Environmental Earth Sciences》2016,75(19):1316

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A comparison of a GCM simulation of the seasonal cycle of the atmosphere with observations part II: Stationary waves and transient fluctuations     

David M. Straus  J. Shukla 《大气与海洋》2013,51(4):575-607

Abstract

This paper presents the seasonal dependence of the stationary and transient eddies of the GLAS/UMD GCM from a two‐year annual cycle integration.

The simulated Northern Hemisphere stationary waves are realistic in winter (below 250 mb) and in spring and fall; in winter a large anomalous ridge over the date‐line is noted above 250 mb. The model does not simulate the winter barotropic trough over eastern Canada. In summer the mid‐latitude stationary waves are poorly simulated (possibly owing to anomalous summer rainfall), but the monsoonal structure in the tropics is captured.

The stationary wave field at 500 mb in the Southern Hemisphere is not well simulated, with the range of season‐to‐season variability being much larger than observed. The zonally averaged stationary wave rms is realistic below 200 mb in winter and spring, but is less so in summer and autumn, possibly due to erroneous summertime precipitation.

The geographical distributions of 500‐mb transient and band‐pass height rms, of transient 850‐mb heat flux and of 200‐mb momentum flux in the Northern Hemisphere are well simulated except for summer. The latitude‐height dependence of height rms and low‐level transient heat flux is realistic in both summer and winter, but the transient momentum flux is not well simulated in summer. The mid‐level transient heat flux is too strong.

The overall pattern of transient activity at 500 mb in the Southern Hemisphere is reasonable in the GCM, although there is too much variability in the eastern Pacific, while the observed peak in rms in the New Zealand sector is displaced eastwards in the GCM. The latitude‐height dependence of transient height rms and transient fluxes of heat and momentum looks quite realistic, and is similar in accuracy to the Northern Hemispheric results.  相似文献   

Erratum to: Use of remote sensing in characterization and management of Dhamni micro-watershed of Chandrapur District of Maharashtra     

Elvis A. Shukla  Jagdish Prasad  M.S.S. Nagaraju  Rajeev Srivastava  D.L. Kauraw 《Journal of the Indian Society of Remote Sensing》2009,37(2):334

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Evaluation of extreme dust storm over the northwest Indo-Gangetic plain using WRF-Chem model     

Shukla  K. K.  Attada  Raju  Khan  Aman W.  Kumar  Prashant 《Natural Hazards》2022,110(3):1887-1910

Natural Hazards - This study uses a high-resolution Weather Research and Forecasting model coupled with the chemistry module (WRF-Chem) to analyze the dust storm that occurred during 12?17...  相似文献