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Nonlinear Dynamics - In this paper, a novel robust tracking control strategy for nonlinear unmatched uncertain systems is formulated using the event-based adaptive dynamic programming (ADP)... 相似文献
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Natarajan Arumugam Abdulrahman I. Almansour Raju Suresh Kumar Mohammad Altaf S.M. Mahalingam Govindasami Periyasami J. Carlos Menéndez Abdul Jaleel Mohammad Ali Al-Aizari 《Tetrahedron letters》2019,60(8):602-605
A series of structurally intriguing novel pyrrolo[3,2-c]quinolinone heterocyclic hybrids have been synthesized for the first time via a one-pot multicomponent domino reaction sequence that involves a 1,3-dipolar cycloaddition and two subsequent annulation steps. Baylis-Hillman adducts derived from various substituted benzaldehyde and methyl acrylate in presence of DABCO were used as a dipolarophiles, while the 1,3-dipole components were azomethine ylides, formed in situ from isatin derivatives and l-phenylalanine. The reaction generated five new bonds, three new rings and four contiguous stereocenters, which were created with full diastereomeric control. 相似文献
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A new third‐order WENO scheme is proposed to achieve the desired order of convergence at the critical points for scalar hyperbolic equations. A new reference smoothness indicator is introduced, which satisfies the sufficient condition on the weights for the third‐order convergence. Following the truncation error analysis, we have shown that the proposed scheme achieves the desired order accurate for smooth solutions with arbitrary number of vanishing derivatives if the parameter ε satisfies certain conditions. We have made a comparative study of the proposed scheme with the existing schemes such as WENO‐JS, WENO‐Z, and WENO‐N3 through different numerical examples. The result shows that the proposed scheme (WENO‐MN3) achieves better performance than these schemes. 相似文献
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Towards Stereoselective Synthesis of the C(31)–C(39) and C(20)–C(27) Fragments of Phorboxazole A 下载免费PDF全文
Kammari Bal Raju Bejjanki Naveen Kumar Bandari Sampath Kumar Kommu Nagaiah 《Helvetica chimica acta》2015,98(3):386-399
The stereoselective synthesis of the C(31)–C(39) and C(20)–C(27) fragments of phorboxazole A ( 1 ) was achieved from commercially available and inexpensive D ‐mannitol. Crimmins aldol reaction and a decarboxylative Claisen‐type reaction are the key steps for the C(31)–C(39) fragment, and L ‐proline‐catalyzed aldol reaction, Sharpless asymmetric epoxidation, and epoxide ring opening reaction with Gilman's reagent are the key steps for the C(20)–C(27) fragment of phorboxazole. 相似文献
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Surapuraju Pavan Kumar Raju Mallikarjun Narayanam Banothu Kranthi Kumar Sreeram Tejaswee Saranjit Singh 《Chromatographia》2015,78(19-20):1245-1250
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Abstract A green and efficient methodology has been developed for the direct conversion of aryl aldehydes to the corresponding tert-butyl peresters. The reaction has been carried out in absence of any solvent and the sunlight is used as the green source of energy. In this reaction tetrabutylammonium iodide (TBAI) acts as the mild organo catalyst and tert-butyl hydroperoxide (TBHP) serve as the source of tert-butyl group. 相似文献