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141.
Hydride Migration from a Triangular Face to a Tetrahedral Cavity in Tetranuclear Iron Carbonyl Clusters upon Coordination of [AuPPh3]+ Fragments 下载免费PDF全文
Dr. Marco Bortoluzzi Dr. Iacopo Ciabatti Dr. Cristina Femoni Dr. Mohammad Hayatifar Prof. Maria Carmela Iapalucci Prof. Giuliano Longoni Prof. Stefano Zacchini 《Angewandte Chemie (International ed. in English)》2014,53(28):7233-7237
Metal hydrides are of fundamental importance in chemistry, both as solid‐state materials and molecular compounds. The first low‐valent molecular metal cluster containing an interstitial four‐coordinate hydride in a tetrahedral site is decribed, which undergoes hydride migration from the surface to the tetrahedral cavity of the cluster upon coordination of a [AuPPh3]+ fragment. The [HFe4(CO)12(AuPPh3)2]? mono‐anion, which contains a surface μ3‐H, was obtained from the reaction of [HFe4(CO)12]3? with two equivalents of [Au(PPh3)Cl]. This is, in turn, transformed into the neutral [HFe4(CO)12(AuPPh3)3] upon addition of a third [AuPPh3]+ fragment, with concomitant migration of the unique hydride from the surface of the cluster to its tetrahedral cavity. All of these species have been fully characterized in solution by means of IR and multinuclear NMR spectroscopy, and in the solid state by single‐crystal X‐ray diffractometry. 相似文献
142.
A concise synthesis of (R)-4-amino-3-hydroxybutanoic acid, starting from L-malic acid, is reported. The approach is based on the conversion of the oxazolidin-2-one 9 into a full protected form of (®)-GABOB by an Arndt-Eistert reaction. 相似文献
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Maurizio Galimberti Stanislao Senatore Lucia Conzatti Giovanna Costa Gaetano Giuliano Gaetano Guerra 《先进技术聚合物》2009,20(2):135-142
The formation of clay intercalates with three different kinds of organic ammonium salts, when mixed in the presence of synthetic or natural polyisoprene rubber, has been investigated. X‐ray diffraction and transmission electron microscopy (TEM) experiments have shown that intercalates with organic bilayers, rather than with interdigitated organic monolayers, are obtained only for the ammonium salts presenting two long alkyl chains and only in the presence of the natural rubber (NR). These results have been qualitatively rationalized on the basis of suitable interlayer densities. Both monolayer and bilayer clay intercalates remain stable for short‐term heating procedures at temperatures lower than 250°C. For treatments at higher temperatures, where the decomposition of the organic ammonium salt occurs, both kinds of clay intercalates maintain intralayer crystalline order. However, the decomposition of the organic modifier leads to the formation of pristine and exfoliated clay for the intercalates with organic monolayers and bilayers, respectively. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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Recently a one-dimensional closed ladder of Josephson junctions has been studied [G. Cristofano, V. Marotta, A. Naddeo, G. Niccoli, Phys. Lett. A 372 (2008) 2464] within a twisted conformal field theory (CFT) approach [G. Cristofano, G. Maiella, V. Marotta, Mod. Phys. Lett. A 15 (2000) 1679; G. Cristofano, G. Maiella, V. Marotta, G. Niccoli, Nucl. Phys. B 641 (2002) 547] and shown to develop the phenomenon of flux fractionalization [G. Cristofano, V. Marotta, A. Naddeo, G. Niccoli, Eur. Phys. J. B 49 (2006) 83]. That led us to predict the emergence of a topological order in such a system [G. Cristofano, V. Marotta, A. Naddeo, J. Stat. Mech.: Theory Exp. (2005) P03006]. In this Letter we analyze the ground states and the topological properties of fully frustrated Josephson junction arrays (JJA) arranged in a Corbino disk geometry for a variety of boundary conditions. In particular minimal configurations of fully frustrated JJA are considered and shown to exhibit the properties needed in order to build up a solid state qubit, protected from decoherence. The stability and transformation properties of the ground states of the JJA under adiabatic magnetic flux changes are analyzed in detail in order to provide a tool for the manipulation of the proposed qubit. 相似文献
147.
Giuliano Artico Roberto Moresco 《Journal of Mathematical Analysis and Applications》1985,107(1):144-147
In this paper we answer two questions raised by M. A. Erceg [J. Math. Anal. Appl. 69 (1979), 205–230]: precisely we show that the fuzzy unit interval is never T0 except in the standard case and that a fuzzy pseudo-metrizable T0 space is metrizable in the sense of Erceg (ibid.); hence the two definitions of metrizable space given in B. Hutton and I. Reilly [Fuzzy Sets and Systems3 (1980), 93–104] and Erceg (ibid.) are equivalent. 相似文献
148.
G. M. Florio B. Ginatempo A. Stancanelli R. Ruggeri E. S. Giuliano 《Il Nuovo Cimento D》1990,12(11):1509-1517
Summary We have investigated the electronic states of some Pt-W alloys by means of the relativistic KKR-CPA theory in order to gain
some insights on the many interesting physical properties of such a system. In particular we were interested in studying the
role of the Fermi surface topology in the ordering phenomena shown by this alloy. It turns out that the broadening of the
states at the Fermi energy makes the Fermi surface concept questionable. Reasons for that are understood in terms of our scheme
and approximations, even though to give an exhaustive answer one should pursue the full-charge self-consistency obtainable
in the SCF-KKR-CPA theory. 相似文献
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150.