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561.
Trends in seasonal temperatures over the Indian region 总被引:1,自引:0,他引:1
Nilesh K Wagholikar K C Sinha Ray P N Sen P Pradeep Kumar 《Journal of Earth System Science》2014,123(4):673-687
An investigation has been carried out to identify the trends in maximum, minimum and mean temperatures and temperature range over the Indian land mass during the winter (January, and February), pre-monsoon (March–May), southwest monsoon (June–September) and post-monsoon (October–December) seasons by using high resolution daily gridded data set prepared by India Meteorological Department for the period of 1969–2005. It has been observed that the maximum temperatures over the west coast of India show rising trend in winter, southwest monsoon and post-monsoon seasons but the maximum temperatures do not show any significant trend over the other parts of the country. Minimum temperatures show increasing trend over the North Indian states in all seasons and they show an increasing trend over the west coast of India in winter and southwest monsoon seasons. Mean temperature shows an increasing trend over the west coast of India during winter and southwest monsoon seasons. Decreasing trend is observed in the temperature range over North India in all seasons due to increasing trend in minimum temperature. 相似文献
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In many developing world economies in recent years, the state has been seen to encourage neoliberal economic expansion policies. This has involved both large-scale foreign corporations and sometimes large-scale domestic corporations. Many studies have discussed the new landscapes of economic hardship and the impacts on small businesses. The aim of this paper is to argue that the impacts on small traders are in fact more complex and varied than usually appears in the literature. The research was conducted in the industrial city of Durgapur in the Bardhaman district of West Bengal, India. First it is argued that the impact has been greatest on the ‘kirana’ owners, operating small convenience type stores with legalized trading arrangements and fixed premises. On the other hand, the street vendors (often unlicensed and having no fixed premises) seem not to be affected in terms of customer loss and indeed could be seen to be doing well against the backcloth of neoliberal expansion. In fact we argue that the growth in the number of street vendors provides as much of a threat to future livelihoods for traditional kirana owners as the growth of large corporations itself. 相似文献
564.
Shift in detrital sedimentation in the eastern Bay of Bengal during the late Quaternary 总被引:1,自引:0,他引:1
C. Prakash Babu J. N. Pattan K. Dutta N. Basavaiah G. V. Ravi Prasad D. K. Ray P. Govil 《Journal of Earth System Science》2010,119(3):285-295
Down-core variations of granulometric, geochemical and mineral magnetism of a 70-cm long sediment core retrieved from the eastern Bay of Bengal abyssal region were studied to understand sedimentation pattern and sediment provenance during the last ~12 kyr BP. Based on down-core physical and elemental variations, three units were identified: unit 3 (70–43 cm) is a ~30 cm thick clayey silt organic carbon-rich (0.5–0.92%) turbidite probably delivered by the Brahmaputra River during the late Quaternary period. Units 2 (43–24 cm) and 1 (24–0 cm) represent enhanced and reduced supply of coarse-grained detrital sediments from the Ganges River during early and late Holocene period, respectively. Increased terrigenous supply dilutes calcium carbonate (CaCO3) and biogenic elements (P, Ba and Cu) in units 3 and 2. On the contrary, a reduction in detrital input enhances CaCO3 and biogenic elements in unit 1. Lithogenic elements (Ti, Al, K and Rb) and shale-normalized REE patterns in all three units suggest terrigenous source. The shift in provenance from the Brahmaputra to the Ganges derived sediments is evident by a sharp increase in sediment grain size, increased concentration and grain size assemblages of magnetic minerals, lithogenic elements concentration and Lan/Ybn ratio. This study highlights terrigenous dilution on biogenic sedimentation in the eastern Bay of Bengal sediments. 相似文献
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The partitioning of trace elements (Sc, Ti, Sr and Sm) between diopsidic clinopyroxene and liquid was studied experimentally in the system diopside-albite-anorthite at 1250°C, 1300°C and 1345°C at 1 atm. Twelve different bulk compositions were selected to study the effects of temperature and chemical composition. A Cameca ion microprobe was used to determine trace element concentrations in both clinopyroxene and liquid. Experiments of different run duration days) showed that equilibrium was approached in less than 4 days at 1275°C. Equilibrium was also evaluated by a reversal run. A series of runs of constant bulk composition but with variable trace element contents showed that Henry's Law was obeyed over concentration ranges of the trace elements similar to those encountered in natural systems. The partition coefficients show significant ranges: Sc, 0.345~2.61; Ti, 0.084~0.214; Sr, 0.075~0.136; Sm, 0.054~0.328; the values are comparable with those obtained experimentally by other investigators. The partition coefficients vary as a function of both temperature and chemical composition. The experimental results are discussed in terms of exchange equilibria using the Bottinga-Weill silicate melt model. It is demonstrated that analytical uncertainties of both major and trace elements play an important role in understanding trace element exchange equilibria; propagation of analytical errors in the thermodynamic treatment is equally important. 相似文献