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1.
4-Methylcoumarins (2), obtained by condensation of suitable phenols (1) with ethyl acetoacetate in the presence of sulfuric acid, lead directly to flavans (3) when refluxed with sodium hydroxide and ethanediol. 相似文献
2.
Dhoolesh Gangaram Kokare Krishna Naik Anupama Nevrekar Avinash Kotian Vinayak Kamat Vidyanand K. Revankar 《应用有机金属化学》2016,30(4):181-187
Mononuclear divalent complexes of Co, Ni, Cu and Zn derived from a benzofuran‐based novel hydrazone tridentate ligand were synthesized and characterized using various spectroscopic methods. Elemental analysis reveals that the metal‐to‐ligand ratio is 1:2 which is supported by mass spectrometry results. Conductivity measurements suggest that all the complexes are non‐electrolytic in nature. The ligand and complexes were evaluated for their antimicrobial potency. Bioassay of all hydrazone chelates shows enhanced activity as compared to that of the ligand. The complex with cobalt ion as the metal centre shows better activity against fungi than the standard. Also, ligand and complexes were screened for antituberculosis activity; some analogues (Ni, Cu, Zn) are eight times more active than the standard. Both ligand and complexes show moderate ability to cleave calf thymus DNA. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Lohar Trushant Mane Ananda Kamat Siddharth Kumbhar Arjun Salunkhe Rajashri 《Research on Chemical Intermediates》2018,44(3):1919-1933
Research on Chemical Intermediates - An efficient and versatile mechanochemical route for the synthesis of chromene and isoindolo[2,1-a]quinazoline scaffolds has been developed via a simple mortar... 相似文献
5.
The Sun is a plasma diffuser that selectively moves light elements like H and He and the lighter isotopes of each element
to its surface. The Sun formed on the collapsed core of a supernova (SN) and is composed mostly of elements made near the
SN core (Fe, O, Ni, Si, and S), like the rocky planets and ordinary meteorites. Neutron emission from the central neutron
star triggers a series of reactions that generate solar luminosity, solar neutrinos, solar mass fractionation, and an outpouring
of hydrogen in the solar wind. Mass fractionation seems to have operated in the parent star and likely occurs in other stars
as well.
The text was submitted by the authors in English. 相似文献
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M. J. Kamat R. Kaimal T. R. Saranathan 《Fresenius' Journal of Analytical Chemistry》1981,307(1):19-20
Summary A d. c. arc Spectrographic method employing the carrier distillation technique has been developed for the determination of the non-rare earth impurities Bi, Cu, Fe, Mg, Mn, Ni, Pb and Sn in Dy2O3 in the range of 1–100 ppm. The sample is ground with 5% AgCl containing 1000 ppm of Ge as internal standard. The average precision of the method in terms of the coefficient of variation of the concentration is 12–15% for the different impurities.
Bestimmung von Verunreinigungen (außer Seltenen Erden) in gereinigtem Dysprosiumoxid — Ein spektrographisches Verfahren mit Hilfe der Trägerdestillation
Zusammenfassung Die Verunreinigungen Bi, Cu, Fe, Mg, Mn, Ni, Pb und Sn werden im Bereich von 1 bis 100 ppm mit Hilfe der Gleichstrombogenanregung bestimmt. Die Dy2O3-Probe wird mit 5 % eines Trägergemisches vermahlen, das aus AgCl mit 1000 ppm Ge (als innerem Standard) besteht. Die durchschnittliche Genauigkeit der Bestimmungen liegt bei 12–15%.相似文献
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Kevin E. O’Shea Ailette Aguila K. Vinodgopal Prashant V. Kamat 《Research on Chemical Intermediates》1998,24(6):695-705
The oxidation of dimethyl methylphosphonate (DMMP) was examined under ultrasonic conditions (640 kHz) in oxygen saturated
aqueous solutions. Acetic acid, formic acid, methylphosphonic acid, phosphate, and oxalic acid have been identified as the
major products produced during the sonolytic irradiation of DMMP. The initial rates of oxidation were determined as a function
of initial DMMP concentration. The kinetic behavior of the system is consistent with the Langmuir-Hinshelwood model implying
oxidative processes occur at or near the gas-liquid interface during cavitation. Mechanistic implications and conclusions
are discussed based on the product distributions and kinetic parameters. 相似文献