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81.
82.
E. Vardaci A. Di Nitto A. Brondi G. La Rana R. Moro P. N. Nadotchy M. Trotta A. Ordine A. Boiano M. Cinausero E. Fioretto G. Prete V. Rizzi D. Shetty M. Barbui D. Fabris M. Lunardon G. Montagnoli S. Moretto G. Viesti N. Gelli F. Lucarelli G. N. Knyazheva E. M. Kozulin 《The European Physical Journal A - Hadrons and Nuclei》2010,43(2):127-130
83.
The reaction of 2-phenyl- and 1-methyl-2-phenylindole with nitrogen dioxide or with nitrous acid (NaNO2-CH3COOH) in benzene leads mainly to the formation of the isonitroso and 3-nitroso indole derivatives, respectively. When reacted with nitrous acid, 1-methyl-2-phenylindole gives also the corresponding azo-bis-indole in good yields. The reaction of indole with nitrogen dioxide leads to 2-(indol-3-yl)-3H-indol-3-one as the main product together with small amounts of 2-(indol-3-yl)-3H-indol-3-oxime; whereas the major product obtained when the same indole is reacted with nitrous acid is represented by 2-(indol-3-yl)-3H-indol-3-oxime. The reaction of 3-alkyl substituted indoles with nitrogen dioxide is rather complex and results in the formation of different nitro indoles, whereas nitrosation is observed when nitrous acid is used. Crystal structures of 2-(indol-3-yl)-3H-indol-3-one and of 4-nitro-N-acetyltryptamine have been determined by X-ray analysis. 相似文献
84.
85.
P. Finetti F. Sedona G.A. Rizzi U. Mick K. Schierbaum G. Granozzi 《Surface science》2010,604(3-4):366-371
We present the results of a XAS experiment carried out at the Ti 2p edge on well-ordered TiOx ultrathin films grown on the Pt(1 1 1) surface. XAS at the Ti 2p edge has been extensively applied to the study of Ti bulk compounds, particularly to the study of titania. According to the literature, the corresponding Ti 2p edge spectral shape is related to the stoichiometry and crystal field symmetry at the Ti sites. In the present study we aim at extending the potential of the XAS technique by discussing Ti 2p spectra obtained on several, dimensionally confined, TiOx phases in the form of ultrathin films. One of the main features of these films is their high degree of structural order. Furthermore, the results of previous studies provide valuable information about the chemistry and structure of the films, so that we are able to analyse the current XAS data in detail and to compare them with the appropriate Ti 2p XAS data of bulk oxides. We find that in the case of ultrathin film with a fully oxidised Ti4+ stoichiometry, the Ti 2p XAS data display features that are very similar to the ones observed in related bulk systems. The XAS data of the reduced TiOx films (with x < 2) show a rather different and specific shape. By comparing the experimental spectra with an atomic type of model calculation we show that the Ti 2p XAS profiles can be attributed mainly to stoichiometry-symmetry effects. 相似文献
86.
A simple and efficient stereoselective synthesis of polysubstituted beta,gamma-epoxyhydroxylamines and 4-hydroxyalkyl-1,2-oxazetidines, based on the addition of alpha-lithiated aryloxiranes to nitrones and subsequent cyclization of the corresponding intermediates in a 4-exo-tet mode, is described. 相似文献
87.
Corrado Marastoni 《Mathematische Nachrichten》2013,286(10):992-1006
Given a pair of dual generalized flag manifolds of a semisimple algebraic group, we show that the integral transform between them given by the open orbit in their product is an equivalence. We also describe the links of this problem with the structure of generalized Verma modules, and how the above construction can be applied to the representation theory of real forms of the group. 相似文献
88.
Journal of Algebraic Combinatorics - A class of scattered linearized polynomials covering infinitely many field extensions is exhibited. More precisely, the q-polynomial over $${{\mathbb... 相似文献
89.
Alessia Bacchi Giorgio Chelucci Manlio Grandino Giovannina Minardi Corrado Pelizzi Giancarlo Pelizzi Costantino Solinas 《Journal of chemical crystallography》1994,24(10):659-663
Cobalt(II), nickel(II), and copper(II) complexes of 2-[(2S)-2-pyrrolidinyllpyridine (L) have been synthesized and characterized. The crystal structure of the complex [Cu(L)2(NO3)]NO3 has been determined by X-ray diffraction. Crystals are monoclinic, space groupP2+, witha=10.766(3).b=7.525(2),c=13.447(4) Å. =104.64(2)°. and Z=2. The structure consists of [Cu(L)2(NO3)]+ cations and NO
3
t-
anions. The copper atom has a distorted trigonal bipyramidal coordination geometry with the two pyrrolidine nitrogens and one nitrate oxygen occupying the equatorial positions and the two pyridine nitrogens at the apices. The crystalline cohesion is ensured by a network of hydrogen bonds involving the pyrrolidine groups as donors and both coordinate and uncoordinate nitrates as acceptors. 相似文献
90.