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K. Gunaseelan ¹, B. C. Paul ², J. Das ³, K. Ismail ³

Affiliations
1 Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, New Brunswick, NJ 08903, US
2 Department of Chemistry, Sankardev College, Shillong, IN
3 Department of Chemistry, North Eastern Hill University, NEHU Campus, Shillong-793 002, IN

Abstract

Electrical conductivity of water/sodium dodecyl sulfate/l-butanol/oil microemulsions having molar ratios of water to surfactant and surfactant to cosurfactant equal to 44 and 0.1144 respectively, was measured at 25°C using eight different oils (octane, benzene, toluene, carbon tetrachloride, chloroform, cyclohexane, m-xylene and nitrobenzene). These microemulsions have been found to fall in the w/o and bicontinuous regions over the range of volume fractions of oils covered in this study. The specific conductivity data were least-squares fitted to a virial expression. In the w/o region the dimensional characteristics of the microemulsions were estimated.

Keywords

Microemulsion, Sodium Dodecyl Sulfate, Butanol, Oil, Electrical Conductivity.

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M. K. Manna ¹, U. P. Samaddar ¹, J. Das ¹

Affiliations
1 Botanical Survey of India, Howrah, IN

Abstract

No Abstract.

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H. K. Kalita ¹, B. Talukdar ¹, R. A. Baishya ¹, S. Basumatary ¹, J. Das ², A. Dutta ¹, R. Ch. Barman ³, D. Sarma ¹

Affiliations
1 Department of Zoology, Gauhati University, Guwahati, Assam, IN
2 Department of Zoology, Goalpara College, Goalpara, Assam, IN
3 NFDB Regional Centre, Campus of NIRD, NERC, Khanapara, Guwahati, IN

Abstract

The study was conducted in a society pond of Gandhibasti village of Abhayapuri, Bongaigaon, Assam to assess the impact of duck droppings on water quality and pond productivity. The pond was integrated with ducks (Anas platyrhynchos) to obtain the benefit of duck litters on the pond productivity and fish growth. The mean dry weight of 80 ducks excreta was estimated as 3.864 kg/ha/day, discharging into the pond. 18,000 fingerlings. Indian major carps along with few exotic carp were stocked in the month of April, 2013. Supplementary feed was also given to the fishes in alternate days to ensure their steady growth. All the studied physico-chemical parameters were found within the permissible limit and the growth of fishes was also satisfactory. The maximum growth was recorded in Catla followed by silver carp, common carp, Rohu and Mrigala.

Keywords

Duck Dropping, Pond Productivity, Indian Major Carps, Integrated Farming.

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S. S. Baral ¹, K. Sharma ¹, A. K. Saraf ¹, J. Das ¹, G. Singh ¹, S. Borgohain ¹, E. Kar ¹

Affiliations
1 Department of Earth Sciences, Indian Institute of Technology, Roorkee 247 667, IN

Abstract

No Abstract.

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S. Borgohain ¹, J. Das ², A. K. Saraf ¹, G. Singh ¹, S. Baral ¹

Affiliations
1 Department of Earth Sciences, Indian Institute of Technology Roorkee, Roorkee 247 667, IN
2 Department of Earthquake Engineering, Indian Institute of Technology Roorkee, Roorkee 247 667, IN

Abstract

The Lohit River is a south bank tributary of the Brahmaputra River. Till 1987, the Lohit River used to meet the Brahmaputra at a place near Bairagi Chapari (27.77°N, 95.44°E). By 1995, the confluence point had shifted about 20 km downstream. One small channel of the Lohit River captured the Dangori River during the 1988 flood. Gradually the Lohit River started flowing along the captured channel. By 1995, it became the trunk channel of the Lohit River and Dibru Saikhowa region became an island. Banklines of Brahmaputra and Lohit rivers have undergone significant changes near their confluence point within the last few decades. By 1987, the south bank of the Brahmaputra near Rohmoria (27.55°N, 95.15°E) shifted about 1.6 km southward from its position in 1973. Interestingly, within the period 1988-90 the south bank shifted about 4.1 km south. This major shifting was the result of capturing of the Dangori River by the Lohit River. However, migration of the rivers towards the south has stopped after 1995. Analysis of SRTM DEM reveals that topographic elevation has played a major role in changing the course of the Lohit River.

Keywords

Banklines, Confluence Point, Morphodynamic Changes, Topographic Elevation, Trunk Channel.

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D. Sarma ¹, J. Das ¹, A. Dutta ¹

Affiliations
1 Department of Zoology, Gauhati University, Guwahati-781 014, Assam, IN

Abstract

Rogor is a commonly used pesticide in the agricultural field. The present study was undertaken to evaluate the lethal toxicity of Rogor, an organophosphorus pesticide, in freshwater fish Channa punctatus (Bloch) and relative behavioural changes after exposing for 96 hours. The regression equation calculated as y = 9.551x + 6.173 and the LC₅₀ value calculated for Channa punctatus was at 0.75 mL/L. During exposure, fish showed faster opercular activity, erecting dorsal and ventral fin, huge secretion of mucus from whole body, etc.

Keywords

Acute Toxicity, Channa punctatus, Rogor, LC₅₀.

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