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991.
The component-mode synthesis method is usually adopted in order to reduce the number of degrees-of-freedom of structures composed of two or more substructures without loosing the main physical characteristics of the whole structure. Many approaches of this method have been proposed in the literature. These approaches differ from each other for the boundary conditions which are imposed at the interface of the two substructures. In this paper four variants of interface boundary conditions are examined. For each set of conditions a suitable coordinate transformation, compatible with the conditions at the boundary degrees-of-freedom between the two substructures, is presented. Moreover, in the numerical applications a comparison between the four component-mode synthesis variants here proposed with respect to the same variants proposed in the literature is presented. The better accuracy of the proposed approach is shown. 相似文献
992.
Giuseppe Giovannelli Lucia D’Urzo Giovanna Maggiulli Stefano Natali Cosimo Pagliara Ivonne Sgura Benedetto Bozzini 《Journal of Solid State Electrochemistry》2010,14(3):479-494
This paper concentrates on a novel approach to the electrochemical treatment of bronze disease, based on the use of room-temperature
ionic liquids (RTIL). In particular, we employed 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide as the electrolyte
for the galvanostatic cathodic treatment of a late bronze-age artifact that had been exposed to marine environment during
its history, dating back to ca. 1100 B.C. After an accurate metallographic and structural analysis of the as-found object—proving,
among other findings, that bronze disease is essentially related to the presence of nantokite locked inside subsurface pits
of typical equivalent diameter of several hundred micrometers, we subjected it to optimal electrochemical conditions, showing—on
the basis of X-ray diffraction—that nantokite could be effectively removed and Cu(I) reduced to metallic Cu. Numerical computations
in the full three-dimensional pit geometry, with realistic nonlinear electrochemical boundary conditions, provide the theoretical
framework for the choice of RTIL—as opposed to aqueous solutions—and for the quantitative evaluation of Cl− removal rates. 相似文献
993.
994.
Ranjith Venkatrama Giuseppe Sergioli Hector Freytes Roberto Leporini 《International Journal of Theoretical Physics》2017,56(12):3860-3868
In this work, we introduce a fuzzy type representation of a quantum version of the Fredkin gate in the framework of quantum computation with mixed states. 相似文献
995.
Antonia Torres Ávila Pimenta Raimundo Braz‐Filho Piero Giuseppe Delprete Elnatan Bezerra de Souza Edilberto Rocha Silveira Mary Anne Sousa Lima 《Magnetic resonance in chemistry : MRC》2010,48(9):734-737
Two unusual monoterpene indole alkaloids, stachyoside ( 1 ) and nor‐methyl‐23‐oxo‐correantoside ( 2 ), have been isolated from the aerial parts of Psychotria stachyoides. The structural elucidation of both compounds was performed by the aid of HRESIMS, FT‐IR, and 1D‐ and 2D‐NMR techniques including COSY, HSQC, HMBC, and NOESY. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
996.
997.
Silvia Todros Chiara Venturato Arturo N. Natali Giuseppe Pace Vito Di Noto 《Journal of Polymer Science.Polymer Physics》2014,52(20):1337-1346
The effect of steam on the micro‐phase structure and mechanical properties of different block copolymers used in biomedical devices is investigated via FT‐IR, tensile tests and dynamic mechanical analysis (DMA). Steam sterilization, commonly performed on medical devices and simulated in this work, affects the copolymers' morphology, due to high temperature and humidity conditions. FT‐IR analysis reveals that steam induces a modification in the crystalline conformations of copolymers with a pre‐existing hydrogen bonding network, that is, thermoplastic polyurethanes (TPU) and poly(ether‐block‐amide) (PEBA), while it does not significantly affect the domain conformation in styrenic block copolymers (SEBS), due to weak interaction with water. As a consequence, relevant changes of the mechanical properties, closely related to the microdomain structure, are found for TPU and PEBA after sterilization, while SEBS mechanical behavior remains stable, as demonstrated by tensile tests and DMA results. For this reason, SEBS is suggested as the best choice in terms of durability in biomedical applications. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 1337–1346 相似文献
998.
Vito Fiandanese Giuseppe Marchese Francesco Naso 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):89-90
Abstract Synthetic, mechanistic, and stereochemical aspects of the reactions of cuprates with various systems are being investigated in these laboratories(1). The series of substrates includes several sulphonyl-activated compounds. 相似文献
999.
1000.