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111.
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Chiara Castiglioni Mariangela Gussoni Juan Teodomiro Lopez Navarrete Giuseppe Zerbi 《Mikrochimica acta》1988,94(1-6):247-249
A preliminary analysis of the spectra of poly-para-phenylene and of a few oligomers (bi to hexa) is reported. Both frequencies and intensities are discussed. 相似文献
114.
Jacques Daunis Grard Del Vecchio Robert Jacquier Hlne Lopez Georges Maury 《Journal of heterocyclic chemistry》1978,15(1):23-27
New systems with five, six or seven membered nitrogen hetero-cycles (pyrazole, pyrimidine or diazepine) simultaneously fused to the 4, 5 and 6 positions of the two A and B rings of a cholestane derivative have been prepared. 相似文献
115.
A metallosupramolecular coordination polyelectrolyte prepared by the reaction of cobalt(II) with a novel bisterpyridine ligand has been assembled as the active component in electrochromic films by sequential deposition using electrostatic layer-by-layer self-assembly. 相似文献
116.
P. Mison R. Chaabouni Y. Diab R. Martino A. Lopez A. Lattes F. W. Wehrli T. Wirthlin 《Magnetic resonance in chemistry : MRC》1976,8(2):79-89
13C chemical shifts for twenty-nine alkyl and phenyl substituted N-unsubstituted aziridines have been measured. Additivity parameters for methyl, phenyl and aziridyl carbons have been derived with the aim of testing the consistency of the assignments made on the basis of chemical shift considerations and off-resonance decoupling information. The observed chemical shifts are discussed in terms of steric and pseudoconjugation effects. 相似文献
117.
A. Lopez M. M. Gauthier R. Martino A. Lattes 《Magnetic resonance in chemistry : MRC》1979,12(7):418-428
Although nitrogen inversion in unsubstituted aziridines has been shown by 1H NMR, it was only possible to study quantitatively the distribution of both invertomers and determine the thermodynamic parameters by a systematic high field NMR study (CAMECA 250 MHz). Thermodynamic parameters have been determined for 32 compounds. In C-aryl aziridines, the steric hindrance of the aromatic group and its variation with other aziridine ring substituents can be studied. These observations are in agreement with a conjugation phenomenon between the aromatic system and the aziridine ring. 相似文献
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Rubin P Cawlfield C Eisenstein BI Karliner I Kim D Lowrey N Naik P Sedlack C Selen M White EJ Wiss J Shepherd MR Besson D Pedlar TK Cronin-Hennessy D Gao KY Gong DT Hietala J Kubota Y Klein T Lang BW Poling R Scott AW Smith A Dobbs S Metreveli Z Seth KK Tomaradze A Zweber P Ernst J Severini H Dytman SA Love W Mehrabyan S Savinov V Aquines O Li Z Lopez A Mendez H Ramirez J Xin B Huang GS Miller DH Pavlunin V Sanghi B Shipsey IP Adams GS Anderson M Cummings JP Danko I Napolitano J He Q Insler J 《Physical review letters》2006,96(8):081802
Using of data collected with the CLEO-c detector, we report on first observations and measurements of Cabibbo-suppressed decays of D mesons in the following six decay modes: pi+ pi- pi0 pi0, pi+ pi+ pi- pi- pi0, pi+ pi0 pi0, pi+ pi+ pi- pi0, eta pi0, and omega pi+ pi-. Improved branching fraction measurements in eight other multipion decay modes are also presented. The measured D --> pi pi rates allow us to extract the ratio of isospin amplitudes A(DeltaI = (3/2) / A(DeltaI = (1/2)) = 0.420 +/- 0.014(stat) +/- 0.016(syst) and the strong phase shift of delta1 = (86.4 +/- 2.8 +/- 3.3) degrees, which is quite large and now more precisely determined. 相似文献