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51.
Gianfranco Denti Scolastica Serroni Giovanni Sindona Nicola Uccella 《Journal of the American Society for Mass Spectrometry》1993,4(4):306-311
Fast-atom bombardment (FAB) mass spectrometry in the negative ionization mode enables the sputtering into the gas phase of the ruthenium complexes [Ru(2,2′-bipyridine[bpy])2(2,5-bis) (pyrydil)pyrazine[dpp])](PF6)2; [Ru(bpy)2,(2,3dpp)](PF6)2;[Ru(bpy)2,(2,3-dpp-Me)]( PF6)3; and [Ru(bpy)2(?-2,3-dpp)]2 RuCl2(PF6)4 as intact radical anions. These data, combined with those avaiiable from the positive FAB spectra allow a full characterization of the analytes. 相似文献
52.
Antonia Sacchi Paolo De Caprariis Luciano Mayol Giovanni De Martino 《Journal of heterocyclic chemistry》1995,32(3):1067-1069
4-Hydroxy-3-phenylprolines were synthesized via 1-acetyl-2,2-diethoxycarbonyl-2,3-dihydro-3-phenyl-1H-pyrrole. Reversed phase hplc resulted in the isolation of the products which were characterized by 1H and 13C nmr spectroscopy. 相似文献
53.
L. Sirleto G. Abbate G. C. Righini E. Santamato 《Applied physics. B, Lasers and optics》1994,58(2):A5-A6
Time-resolved vibrational spectroscopy
Call for papers 相似文献54.
Giovanni Monegato 《Numerical Algorithms》1996,11(1):271-283
We consider the numerical solution of second kind integral equations of the form $$u(y) - \int\limits_0^1 {k(y/x)\frac{{u(x)}}{x}dx = f(y), 0 \le y \le 1,} $$ for some given kernelk(t). These equations, usually indicated as of Mellin type, arise in a variety of applications. In particular, we examine a Nyström interpolant based on the following product quadrature rule: $$\int\limits_0^1 {k(y/x)\frac{{u(x)}}{x}dx \approx \sum\limits_{i = 0}^n {w_{ni} (y)u(x_{mi} ).} } $$ This rule is obtained by interpolatingu(x) by the Lagrange polynomial associated with the set of Gauss-Radau nodes {x ni}. Under certain assumptions on the kernelk(t), we are able to prove the stability of our interpolant and derive convergence estimates. 相似文献
55.
A (k,k)-current T on an open subset of CN is plurisubharmonic if is positive. Positive plurisubharmonic currents admit Lelong numbers; we prove here that they are independent on the coordinates system. Moreover, if Y is an analytic subset of pure dimension, then the Lelong numbers of T on Y are given by a non negative weakly plurisubharmonic function. 相似文献
56.
57.
58.
Giovanni Gaiffi 《manuscripta mathematica》1996,91(1):83-94
Let
be the complexified Coxeter arrangement of hyperplanes of typeA
n−1. In this paper we construct anS
n+1 extension of the naturalS
n action on the complex cohomology ring of the complement ofA
n−1. Recurrence formulas connecting characters with respect to theS
n and theS
n+1 action are given. 相似文献
59.
Di-2-pyridylketone semicarbazone as ligand in metal complexes: synthesis and X-ray crystal structure
Luigi P. Battaglia Pier Giovanni Berzolla Anna Bonamartini Corradi Corrado Pelizzi 《Journal of chemical crystallography》1993,23(12):973-979
A series of complexes of di-2-pyridylketone semicarbazone (Hdips) and Mn(II), Co(II), Co(III), Ni(II) and Cu(II) nitrates were synthesized and characterized by means of IR spectroscopy and for cobalt and nickel by X-ray crystal structures. The results are in agreement with the formulae: Mn(Hdips)2(NO3)2·2H2O, [Co(Hdips)2](NO3)2·H2O (I), [Ni(Hdips)2](NO3)2·H2O (II), Cu(Hdips)(NO3)2·2H2O, [Co(dips)2](NO3)·2H2O (III). The structure of I and II are monoclinic, space groupP21/c, with, I,a=15.980(4),b=11.531(2),c=16.170(2)Å;=104.20(2)°,Z=4,R=0.032; II,a=16.109(5),b=11.480(3),c=16.135(6)Å;=104.15(2)°,Z=4,R=0.069. Compound III is also monoclinic, space groupP21/c witha=12.173(5),b=15.619(5),c=15.338(8)Å;=111.40(4)°,Z=4,R=0.059. In these complexes the ligand is tridentate via carbonylic oxygen, semicarbazone and pyridine nitrogens forming each two five membered chelate rings with the metal in a distorted octahedral geometry. 相似文献
60.
Armentano D De Munno G Mastropietro TF Julve M Lloret F 《Journal of the American Chemical Society》2005,127(31):10778-10779
Intermolecular proton transfer in solid phase from the hydroxo bridge to a water molecule occurs in a new mu-hydroxo iron(III) compound of formula {EtNH3[Fe2(ox)2Cl2(mu-OH)].2H2O}n leading to a still crystalline compound in which the mu-oxo bridge replaces the mu-hydroxo one. Both three-dimensional compounds exhibit magnetic ordering at Tc ca. 70 K due to a spin canting. 相似文献