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Suma C. Pemmaraju Deepak Sharma Nivedita Singh Richa Panwar Swaranjit S. Cameotra Vikas Pruthi 《Applied biochemistry and biotechnology》2012,167(5):1119-1131
The indigenous microbial community utilizing aliphatic, aromatic, and polar components from the oily sludge as sole source of carbon and energy was selected from the soil samples of Ankleshwar, India for biosurfactant production. Evaluation of biosurfactant production was done using screening assays such as surface tension reduction, hemolytic activity, emulsification activity, drop-collapse assay, and cell surface hydrophobicity studies. Maximum biosurfactant (6.9?g/l) production was achieved after 5?days of growth from Bacillus subtilis DSVP23 which was identified by 16S RNA technique (NCBI GenBank accession no. EU679368). Composition of biosurfactant showed it to be lipopeptide in nature with 15.2% protein content and 18.0% lipid content. Functional group analysis was also done by using Fourier transform infrared spectroscopy which showed it to be a protein-bound lipid thereby imparting them special properties. Analysis by matrix-assisted laser desorption/ionization time-of-flight mass spectrometric and nuclear magnetic resonance revealed that the major constituents of lipopeptide are leucine and isoleucine. Gas chromatographic analysis data indicated that oily sludge components of chain length C12?CC30 and aromatic hydrocarbons were degraded effectively by B. subtilis DSVP23 after 5?days of incubation. These results collectively points toward the importance of B. subtilis DSVP23 as a potential candidate for bioremediation studies. 相似文献
444.
M. S. Murali D. R. Raut D. R. Prabhu P. K. Mohapatra B. S. Tomar V. K. Manchanda 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(3):611-616
Efficacy of chlorinated cobaltdicarbollide in a modified diluent, 20% nitrobenzene in xylene was tested for the extraction
and recovery of Cs from simulated high-level waste (HLW) solutions generated from PHWR-fuel reprocessing. Concentration of
the reagent, composition of the diluent, numbers of contacts, the nature of stripping agents are some of the parameters optimized
for the complete removal of Cs from such waste solutions. The above solvent extraction procedure can be applied to genuine
HLW solutions for effective reduction of the dose due to Cs so that HLW can be handled in fume hoods for its characterization. 相似文献
445.
Bhupendra Singh Tomar 《Journal of Radioanalytical and Nuclear Chemistry》2014,301(3):909-909
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The main contribution of this work is to classify the solution region including data extrema for which high‐order non‐oscillatory approximation can be achieved. It is performed in the framework of local maximum principle (LMP) and non‐conservative formulation. The representative uniformly second‐order accurate schemes are converted in to their non‐conservative form using the ratio of consecutive gradients. Using the local maximum principle, these non‐conservative schemes are analyzed for their non‐linear LMP/total variation diminishing stability bounds which classify the solution region where high‐order accuracy can be achieved. Based on the bounds, second‐order accurate hybrid numerical schemes are constructed using a shock detector. The presented numerical results show that these hybrid schemes preserve high accuracy at non‐sonic extrema without exhibiting any induced local oscillations or clipping error. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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H.M. Meshram Pramod B. Thakur B. Madhu Babu Vikas M. Bangade 《Tetrahedron letters》2012,53(14):1780-1785
A very rapid, convenient, and general method for the synthesis of α-oxo thiocyanates has been described by using clay supported ammonium thiocyanate. The procedure avoids the use of additional catalyst, solvent, aqueous work-up and the yields are high. Moreover, the method is applicable for a variety of aryl, heteroaryl, alkyl α-halo carbonyls, β-keto tosylates, α-halo β-dicarbonyl, α-tosyl, β-dicarbonyl, alkyl halide, and alkyl tosylates. 相似文献
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Jagjeet Kaur Yogita Parganiha Vikas Dubey Deepti Singh 《Research on Chemical Intermediates》2014,40(8):2837-2858
The present review deals with the synthesis and characterization of different phosphors used in medical imaging. A comparative study of different synthesis methods and characterization is presented. The best method for synthesized phosphor is the solid state method because the morphology of the sample is very good. The photostimulated luminescence of the prepared sample has been represented by different authors. The best phosphor used in medical imaging is BaBrCl:Eu2+. 相似文献