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91.
Gaetano Villari 《Annali di Matematica Pura ed Applicata》1965,69(1):191-200
Sommario Si studia il fenomeno della persistenza di soluzioni periodiche per una classe di sistemi di tre equazioni differenziali ordinarie
soggetti a particolari perturbazioni, e si stabilisce un criterio di esistenza di soluzioni periodiche che estende un analogo
risultato valido per equazioni del terz ordine.
Ricerca eseguita nell'ambito del Gruppo di Ricerca n. 11 del C. N. R. 相似文献
92.
Gaetano Fichera 《Milan Journal of Mathematics》1979,49(1):19-48
The paper is concerned with results obtained in the problem consisting in determining the qualitative properties of the electric density and of the electric field originated by a load in equilibrium on a closed surface. In particular the asymptotic behaviour of both of them near the points and the edges of the conducting surface are studied. 相似文献
93.
Synthesis of sulphur containing fused ring heterocycles by intramolecular 1,3-dipolar-cycloadditions
Luisa Garanti Alberto Locatelli Gaetano Zecchi 《Journal of heterocyclic chemistry》1976,13(3):657-659
Sulfur containing fused triazoles and pyrazoles are synthesized through intramolecular cycloadditions of properly functionalized azides and nitrileimines, respectively. 相似文献
94.
95.
Luigi P. Battaglia Anna Bonamartini Corradi Francesco A. Devillanova Gaetano Verani 《Transition Metal Chemistry》1979,4(4):264-266
Summary The crystal structure of the title compound has been determined from x-ray diffractometer data by the heavy-atom method and refined anisotropically by least-squares calculations. Crystals are monoclinic, space groupP 21/c, with unit cell dimensions:a=7.321(1),b=14.622(2),c=14.827(2) Å,=92.95(2), Z=4. The finalR index is 4.6%. The copper coordination is trigonal, involving the sulphur atoms of twoN-ethyl-1,3-imidazolidine-2-thione molecules and one chlorine atom. The structure is held together by two intramolecular N-HCl hydrogen bonds and by normal van der Waals interactions. 相似文献
96.
Francesco A. Devillanova Gaetano Verani Luigi P. Battaglia Anna Bonamartini Corradi 《Transition Metal Chemistry》1980,5(1):362-364
Summary New complexes of copper(I) withN,N-dialkylsubstituted imidazolidine-2-thione ligands were prepared by reduction of CuX2 (X = Cl or Br). The i.r. spectra show that in all the complexes the ligand coordinates through the sulphur atom. The crystal structure of chloro-bis(N,N-dimethylimidazolidine-2-thione)copper(I) has been determined from x-ray diffraction data. Crystals are monoclinic. space groupC
2, with unit cell dimensions:a = 16.022(15),b = 9.942(10),c = 15.112(15) A, = 139.84(10)2, Z = 4. The final R index is 5.2%. The copper coordination is trigonal, involving sulphur atoms of the two ligands and One chlorine atom. The steric effect of the two methyls imposes a rotation of the imidazolidine rings with respect to the coordination plane. The dihedral angle between the mean plane of thiourea moieties. parallel one with the other. and the coordination plane is 119.3°.This work was supported by the National Research Council (C.N.R.) of Rome. 相似文献
97.
Alberghina G Cozzolino R Fisichella S Garozzo D Savarino A 《Rapid communications in mass spectrometry : RCM》2005,19(14):2069-2074
The verification of the cDNA-deduced sequence of the high molecular weight glutenin subunit 1Bx7 in Chinese Spring cultivar was achieved by direct matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) analysis of the tryptic fragments. The published sequence of the 1Bx7 subunit contains 5 Lys and 15 Arg residues but, due to the presence of three Arg-Pro bonds, which are generally resistant to cleavage by trypsin, or cleaved to a very limited extent by trypsin, 19 peptides can be predicted. The identification of the tryptic fragments was achieved by direct MALDI-MS analysis by using three different matrices (DHB, SA and HCCA) in combination with the most compatible sample preparation procedures in order to obtain the maximum sequence coverage. MALDI analysis of the 1Bx7 tryptic digest resulted in the identification of the expected peptides and additional fragments arising from non-specific cleavages; the fragments that were not detected are peptides with low mass (from 147.2 to 317.4), so we obtained a sequence coverage of 98.8%. The results reported here also indicated that the sequence of the 1Bx7 subunit from cv. Chinese Spring is different from the cDNA-deduced sequence reported in the literature; in particular, a possible insertion of the hexapeptide QPGQGQ within the sequence Gln630-Tyr725 was suggested. Finally, it is possible to rule out glycosylation of the 1Bx7 subunit, or any other post-translational modification, to within the detection limits of the method. 相似文献
98.
Franco Cristiani Francesco A. Devillanova Angelo Diaz Gaetano Verani 《Transition Metal Chemistry》1982,7(2):69-71
Summary OsO4 reacts with imidazolidine-2-thione and itsN-methyl andN-ethyl derivatives in acidified 11 vol. H2O:EtOH to give [OsL6]3+. Complexes obtained in the presence of HClO4 or HBF4 have been isolated as crystals and characterized by elemental analysis, i.r. spectroscopy and magnetic measurements.All the ligands bind the metal through the sulphur atom and the magnetic measurements are consistent with low spin osmium(III). The kinetics of [OsL6]3+ formation has been followed spectrophotometrically. Thepseudo-first order rate constants are linear both with respect to the acid and the ligand concentrations, indicating that the kinetically significant process involves one proton and one molecule of the ligand. A comparison of these results with those obtained for the analogous reaction with thiourea is reported. 相似文献
99.
Gaetano Villari 《Annali di Matematica Pura ed Applicata》1960,51(1):301-328
Sunto è contenuto nel n. 1 della Memoria.
A Giovanni Sansone nel suo 70mo compleanno. 相似文献
100.
Ultrathin ordered titanium oxide films on a Pt(111) surface have been prepared by reactive deposition and characterized by low-energy electron diffraction and scanning tunneling microscopy (STM). According to the postdeposition annealing condition, three different phases have been prepared which show a wagon-wheel-like (hereafter ww) morphological pattern. Two of them can be prepared as single phases (w- and w'-TiO(x)) and one (w(int)-TiO(x)) as a mixed phase which always coexists with at least one of the other two phases. All of them are formed by a Ti-O bilayer, where the Ti atoms are located at the interface with the substrate, but they show a rather distinct STM ww pattern. The experimental STM contrast has been discussed on the basis of a Moiré-like model, i.e., as deriving from a modulation of the Ti occupancy of the different substrate sites (i.e., hollow, bridge and on-top sites). The major part of the STM data can be easily interpreted on the basis of this simplified model. 相似文献