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Deepak Basyal 《BSHM Bulletin: Journal of the British Society for the History of Mathematics》2020,35(3):189-206
The Rana regime (1846–1951) in Nepal is widely known for its lack of support for public education and its notorious opposition to women's rights. Near the end of that regime, a mathematical textbook composed in the form of poetic verses was published in the Nepali language, purportedly written by a female author. This article explores the provenance, presentation style, authorship mystery, and unique mathematical content of this book. Furthermore, we explore how mathematical problems may reveal socio-cultural aspects of a country, and how original historical sources such as the one examined in this paper can be useful in the teaching and learning of mathematics today. 相似文献
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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
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Kanchan L. Yadav Deepak K. Rahi Sanjeev K. Soni 《Applied biochemistry and biotechnology》2014,172(4):1898-1908
In recent years, a significant interest has been generated in discovering and developing exopolysaccharides (EPS) produced by microorganisms, especially fungi due to their multifaceted industrial and pharmacological applications. A number of filamentous and cellular fungi have been explored for this; however, according to the existing literature, the work on exopolysaccharide production by indigenous culture on this aspect is still very less and requires a serious attention. The present work is an attempt in this regard and aims to optimize the submerged culture conditions to produce the exopolysaccharides from an indigenous yeast Aureobasidium pullulans RYLF-10 with respect to several operating parameters in shake flask fermentation. The yeast A. pullulans RYLF-10 was identified by 18s RNA sequencing and detailed study on its nutritional requirements, and environmental conditions for submerged culture have been optimized. The optimal temperature and pH for both the vegetative growth and EPS production were found to be 28?±?1 °C and 5.0, respectively, while the agitation speed and inoculum size were reported to be 150 rpm and 1 % (v/v), respectively. Sucrose (50 g/l) and yeast extract (1 g/l) were found to be the most suitable carbon and nitrogen sources which worked best in the ratio of 60:1 and resulted in the maximum EPS yield. Similarly, the other variables like growth regulator (riboflavin) and minerals (NaCl?+?K2HPO4?+?MgSO4) altogether resulted in a noteworthy EPS yield of 45.24 g/l which is the maximum yield from this indigenous isolate of A. pullulans RYLF-10. 相似文献
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α‐Bromination of alkanones with bromine catalyzed by in situ–generated zinc bromide from zinc dust and bromine in water is investigated. Bromination with dioxane‐dibromide as a source of bromine does not require zinc dust and provides selectively α‐mono and α,α‐dibromo products in excellent yields when water is used as solvent. 相似文献
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Avinash Kumar Deepak Kumar K. S. Rao J. Kumar B. Singh A. K. Sharma P. M. Ravi 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(1):421-427
Prediction of downwind tritium air concentrations in the environment around Narora Atomic Power Station was studied on the
basis of Gaussian plume dispersion model. The tritium air concentrations by field measurement [measured tritium air concentrations
in the areas adjacent to NAPS] were compared with the theoretically calculated values (predicted) to validate the model. This
approach will be useful in evaluating environmental radiological impacts due to standard pressurised heavy water reactors. 相似文献