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61.
High diastereoselectivity (>94%) has been achieved in the phenylMgBr addition process to chlorophenyl aldimine derived from the new and sterically hindered triisopropylbenzene sulfinamide (TIPBSA) in the synthesis of a key intermediate of (S)-Cetirizine. Surprisingly, under the same reaction conditions, toluenesulfinamide derived chlorophenyl aldimine provided only 10% ee.  相似文献   
62.
The reported double transition in the series Ce(Fe1–xCox)2 for x<0.3 has been shown to be due to spin reorientation from Mossbauer measurements at57Fe. It is suggested that the competing interactions with randomly substitution of Fe by Co atoms causes a quasi random freezing which results in abrupt loss of magnetization.  相似文献   
63.
Results are presented for study of nonlinear magnetization of a sintered YBa2Cu3O7−y pellet of different thickness of a sample subjected to very low magnetic field. On cooling the sample belowT c in zero field a change, in the oscillatory structure of harmonics in increasing dc field is observed in very low ac magnetic field. The effect of finiteness of the sample on the oscillatory structure and on the hysteresis of harmonics is also studied. The results are explained qualitatively.  相似文献   
64.
Polymers were successfully used in the packaging of waveguide-based photonic components in the area of fiber-to-waveguide coupling, waveguide die attachment, strain relief, and waveguide encapsulation. The application results of these polymers were described in this paper.  相似文献   
65.
A new dicationic asymmetric phase-transfer catalyst, designed by combining chiral elements, is described. Catalytic testing using standard glycine imino ester alkylations shows good yields and moderate enantioselectivities.  相似文献   
66.
The first example of a pair of interconvertible diastereomeric epimers 2α/2β-hydroxy-2-p-hydroxybenzyl-3(2H)-benzofuranone-7-C-β-d-glucopyranoside isolated from the heartwood of Pterocarpus marsupium is reported. The predominance of 1a over 1b was supported by dynamic exchange rates and activation parameters obtained from NMR studies. The mechanism of this unique phenomenon is thought to be operative by the formation of diketone as suggested by deuterium exchange.  相似文献   
67.
A new asymmetric phase-transfer catalyst, designed by combining the chiral building blocks styrene oxide and 2,5-dimethylpyrroline, is described. Catalytic testing using standard glycine imino ester alkylations shows good yields and moderate to good enantioselectivities with a surprising change in enantioselectivity over the course of the reaction. Alkylation of the β-hydroxyl group lead to catalysts with improved selectivity and a larger change in enantioselectivity during the reaction.  相似文献   
68.
69.
Chalcones have been found to undergo facile reduction on treatment with sodium borohydride-nickel chloride system in dioxan-methanol medium to afford dihydrochalcones.  相似文献   
70.

In this digital era, data is new oil and artificial intelligence (AI) is new electricity, which is needed in different elements of operations management (OM) such as manufacturing, product development, services and supply chain. This study explores the feasibility of AI utilization within an organization on six factors such as job-fit, complexity, long-term consequences, affect towards use, social factors and facilitating conditions for different elements of OM by mining the collective intelligence of experts on Twitter and through academic literature. The study provides guidelines for managers for AI applications in different components of OM and concludes by presenting the limitations of the study along with future research directions.

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