Browsing by Author "S.L. Gupta"

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Acid and alkaline phosphatase activity in the cyanobacterium Anacystis nidulans under copper stress
(Springer Netherlands, 1983) S.L. Gupta
The effect of lethal concentration of copper ions on the activities of acid and alkaline phosphatases was investigated in the cyanobacterium Anacystis nidulans and the cyanophage AS-1 resistant mutant. When the level of phosphate declined in the medium, the cells were induced to form alkaline phosphatase (periplasmic protein) and acid phosphatase (cytoplasmic protein). In the presence of copper, the level of enzymes was low, suggesting that synthesis and activity were not completely abolished by copper. This may be related to the permeability of cell membrane. © 1983 Institute of Microbiology, Academy of Sciences of the Czech Republic.
Effect of lethal copper concentrations on nitrate uptake, reduction and nitrite release in Anacystis nidulans.
(1982) A.K. Kashyap; S.L. Gupta
Results suggest that Cu2+ specifically inhibits at the level of nitrite assimilation. -from Authors
High spin states in 164Lu
(American Physical Society, 1996) P. Juneja; S.L. Gupta; S.C. Pancholi; Ashok Kumar; D. Mehta; L. Chaturvedi; S.K. Katoch; S. Malik; G. Shanker; R.K. Bhowmik; S. Muralithar; G. Rodrigues; R.P. Singh
High spin states in the odd-odd 164Lu nucleus have been investigated for the first time, through in-beam gamma-ray spectroscopy, following the 150Sm(19F,5n) reaction at beam energy Elab=105 MeV. Four bands, including two signature split bands are identified. The interpretation of the experimental results is discussed in comparison with the existing data in the neighboring nuclei and in the framework of the cranked shell model. The πh11/2⊗13/2 yrast band exhibits anomalous signature splitting and signature inversion is observed at a spin of 18ℏ. This provides the missing datum for the systematics of staggering and signature inversion for the neighboring odd-odd N=93 isotones and supports the predictions of angular-momentum projection calculations by Hara and Sun. In the second signature split πh 11/2⊗vh9/2 band, the AB neutron crossing occurs at a rotational frequency of ≃0.29 MeV. This is indicative of the disappearance of the blocking effect of the odd neutron.
High-spin states in odd-odd 168Lu
(Springer New York, 1999) S.K. Katoch; S.L. Gupta; S.C. Pancholi; D. Mehta; S. Malik; G. Shanker; L. Chaturvedi; R.K. Bhowmik
High-spin states in the odd-odd 168Lu nucleus, populated in the 154Sm(19F,5n) reaction at a beam energy of 96 MeV, were investigated using in-beam 7-ray spectroscopy techniques. The BC neutron crossing in the yrast band, based on πg7/2[404]7/2+ ⊗ νi13/2[642]5/2+ configuration, occurs at (Latin small letter h with stroke sign)ω=0.31 MeV. The two side bands, based on πh11/2[514]9/2- ⊗ νi13/2[642]5/2+ and πh9/2[541]1/2- ⊗ νi13/2[642]5/2+ configurations, show anomalous signature-splitting and signature-inversion in the first one, to occur at (Latin small letter h with stroke sign)ω=0.24 MeV. A moderately delayed BC-crossing is anticipated in the second one.
Investigation of the corrosion inhibition effect of 3-methyl-6-oxo-4-(thiophen-2-yl)-4,5,6,7-tetrahydro-2H-pyrazolo[3,4-b]pyridine-5-carbonitrile (TPP) on mild steel in hydrochloric acid
(Taylor and Francis Ltd., 2016) Priyanka Singh; M.A. Quraishi; S.L. Gupta; A. Dandia
The corrosion inhibition effect of the synthesized compound 3-methyl-6-oxo-4-(thiophen-2-yl)-4,5,6,7-tetrahydro-2H-pyrazolo[3,4-b]pyridine-5-carbonitrile (TPP) on the corrosion of MS in 1 M HCl was investigated using weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) methods. The results obtained for TPP showed a good inhibition effect on the MS in the 1 M HCl solution. The inhibition efficiency was found to increase with a corresponding increase in the TPP concentration, and the best inhibition of 96.83% occurred at a TPP concentration of 200 ppm. The potentiodynamic polarization studies revealed that TPP behaved as mixed-type of inhibitor that predominantly inhibited the cathodic reaction. The impedance parameters were indicative of the high inhibitory efficiency and the adsorption of TPP on MS. Amongst the Frumkin, Temkin and Langmuir isotherms, the studied compound more closely followed the Langmuir adsorption isotherm. The scanning electron microscopy (SEM) examinations of the electrode surface confirmed the existence of such an adsorbed film. © 2015 The Authors.
Responses of blue-green algae to copper: A comparative study
(1985) S.L. Gupta; A.K. Kashyap; A.P. Singh
The toxic effect of copper sulphate on various forms of cyanobacteria (blue-green algae) ranging from unicellular (Anacystis nidulans, Aphanothece stagnina, Microcystis aeruginosa), filamentous non-heterocystous (Phormidium mucicola, Plectonema boryanum) to filamentous heterocystous (Nostoc muscorum, Anabaena cylindrica) were investigated. While resistance to copper was found to be strain specific property, unicellular algae, in general, were relatively more sensitive than the filamentous forms. There was precise influence of the nitrogen status on the survival of heterocystous forms.