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1.
2.
S Ponnusamy 《Proceedings Mathematical Sciences》1994,104(2):397-411
Denote byS
* (⌕), (0≤⌕<1), the family consisting of functionsf(z)=z+a
2z2+...+anzn+... that are analytic and starlike of order ⌕, in the unit disc ⋎z⋎<1. In the present article among other things, with very
simple conditions on μ, ⌕ andh(z) we prove the f’(z) (f(z)/z)μ−1<h(z) implies f∈S*(⌕). Our results in this direction then admit new applications in the study of univalent functions. In many cases these results
considerably extend the earlier works of Miller and Mocanu [6] and others. 相似文献
3.
Fragmentation patterns resulting from electron impact ionization of 3-(2′-hydroxyethyl)quinolin-2(1H)-one, three of its monosubstituted derivatives and four of its disubstituted derivatives were studied. The molecular ion of quinolinone-2-etbanol undergoes initial fragmentation with the loss of OH·, H2O, CO, ·CHO, CH2O, CH2OH·, CH2?CHOH and HCNO species. The [M – CHO]+ ion is tentatively suggested to have been formed by the expulsion of H· from the [M – CO]+· ion and the [M - CHO]+ peak may be considered as diagnostic of a 2-quinolone-3-ethanol. 相似文献
4.
A new and convenient synthesis of 2-isopropylfuro-(2,3-b)quinolines () from 3-(3-methylbut-1-enyl)-2-quinolones () is described. A neat synthesis of the alkaloids (±)-lunacrine (), (±)-lunasine () and (±)-demethoxylunacrine () is also reported. 相似文献
5.
[reaction: see text] A novel and powerful reagent system R(3)Al-R'(3)SiOTf for the one-pot alkylation-silylation reaction of epoxides was discovered, and the reactions of various epoxides with the new reagent system have been demonstrated to occur stereospecifically giving rise to the corresponding alkylation-silylation products in excellent yields. 相似文献
6.
Raquel Simancas Anand Chokkalingam Shanmugam P. Elangovan Zhendong Liu Tsuneji Sano Kenta Iyoki Toru Wakihara Tatsuya Okubo 《Chemical science》2021,12(22):7677
Zeolites have been successfully employed in many catalytic reactions of industrial relevance. The severe conditions required in some processes, where high temperatures are frequently combined with the presence of steam, highlight the need of considering the evolution of the catalyst structure during the reaction. This review attempts to summarize the recently developed strategies to improve the hydrothermal framework stability of zeolites.This review attempts to summarize the recently developed strategies to improve the hydrothermal framework stability of zeolites. 相似文献
7.
We prove several improved versions of Bohr’s inequality for the harmonic mappings of the form , where is bounded by 1 and . The improvements are obtained along the lines of an earlier work of Kayumov and Ponnusamy, i.e. (Kayumov and Ponnusamy, 2018) for example a term related to the area of the image of the disk under the mapping is considered. Our results are sharp. In addition, further improvements of the main results for certain special classes of harmonic mappings are provided. 相似文献
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10.
Shanmugam Kotteswaran Sundaramoorthy Kannadhasan Perumalsamy Ramasamy 《Journal of Solid State Electrochemistry》2021,25(7):1949-1958
Journal of Solid State Electrochemistry - The phenyl-conjugated oligoene dye 2-cyano3-(4-diphenylaminophenyl)prop-2-enoic acid (SKS) was synthesized by chemical method, and its structure was... 相似文献