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91.
Chemical investigation of the rhizomes of Costus speciosus led to the isolation of a new compound, 22-ketocholesteryl palmitate (1) along with four known compounds, 24-methylenecycloartanol (2), cycloartanol (3), stigmasterol (4) and linoleic acid (5). The structure of new compound was characterised by extensive 1D-, 2D-NMR and mass spectrometry (GC-MS and HR-ESI-MS) techniques. 相似文献
92.
93.
A general gauge-invariant formalism for parallel transport, geodesics and geometric phase based on the pure state density operator is propounded. A single-query quantum search algorithm is proposed. 相似文献
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95.
Selective and controlled aerobic oxidation of activated benzyl alcohols to the corresponding aldehydes is achieved in refluxing CH3CN using catalytic amounts of MoO2Cl2(L)2 where L is DMSO, DMF or THF. The catalysis reactions are possible under open air in the absence of any other external co‐oxidants. However, bubbling of oxygen to the reaction mixture is useful in making the catalysis reaction sustained. Both activated and deactivated varieties of α‐substituted benzyl alcohols (secondary alcohols) give ketones in the same reaction conditions. The inexpensive catalyst is selective towards activated primary benzyl alcohols and also, being mild, stops the oxidation at the aldehyde stage, making it synthetically useful. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
96.
This paper considers the problem of finding limits for a statistical process control (SPC) chart for the process mean, when the process distribution is unknown. The bootstrap method estimates these limits relying on Monte Carlo methods, which are subject to simulation errors. Therefore this paper develops a computationally efficient enumeration method for exact calculations of the control limits. 相似文献
97.
Nagar V. Kar R. Pansare-Godambe L. Chand N. Bute A. Bhale D. Rao A. V. S. S. N. Shashidhar R. Maiti Namita 《Plasma Chemistry and Plasma Processing》2022,42(5):1115-1126
Plasma Chemistry and Plasma Processing - Traditional disinfection methods against pathogens have numerous shortcomings, and inventive methods like cold plasma are required for virus inactivation.... 相似文献
98.
JPC – Journal of Planar Chromatography – Modern TLC - The Ziziphus fruits are recognized as a rich source of biologically active compounds, such as polysaccharides, phenolics,... 相似文献
99.
Mehta Aarti Srivastava A. K. Gupta Govind Chand Suresh Sharma Shailesh Narain 《Journal of Sol-Gel Science and Technology》2021,99(2):295-314
Journal of Sol-Gel Science and Technology - In this article, the beneficial effect of surface passivation rendered by the amalgamation of co-ordinating tri-n-octylphophine (TOP), oleylamine (OLA),... 相似文献
100.