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51.
Castellano M Fortea-Pérez FR Stiriba SE Julve M Lloret F Armentano D De Munno G Ruiz-García R Cano J 《Inorganic chemistry》2011,50(22):11279-11281
Self-assembly of the rigid rodlike ligand N,N'-4,4'-diphenylethynebis(oxamate) (dpeba) and Cu(2+) ions affords a novel dinuclear copper(II) metallacyclophane (nBu(4)N)(4)[Cu(2)(dpeba)(2)]·4MeOH·2Et(2)O (1) featuring a very long intermetallic distance (r = 15.0 ?). Magnetic susceptibility measurements for 1 reveal a moderately weak but nonnegligible intramolecular antiferromagnetic coupling between the two metal centers across the double para-substituted diphenylethynediamidate bridge (J = -3.9 cm(-1); H = -JS(1)S(2), where S(1) = S(2) = S(Cu) = (1)/(2)). Density functional electronic structure calculations on 1 support the occurrence of a spin polarization mechanism. 相似文献
52.
Donatella Donatelli Konstantina Trivisa 《Archive for Rational Mechanics and Analysis》2007,185(3):379-408
We consider a multidimensional model for the combustion of compressible reacting fluids. The flow is governed by the Navier–Stokes
in Eulerian coordinates and the chemical reaction is irreversible and is governed by the Arrhenius kinetics. The existence
of globally defined weak solutions is established by using weak convergence methods, compactness and interpolation arguments
in the spirit of Feireisl [16] and P.L. Lions [24]. 相似文献
53.
A. Bertolini G. Carelli A. Moretti F. Strumia M.X. Qiu R. Corbalan C.M. Cojocaru 《Infrared Physics & Technology》1997,38(7):437-442
Eight new optically pumped far infrared laser transitions from ethyl bromide and 22 from trioxane are presented. For each new line we give the wavelength, the polarization relative to that of the pump laser and the absorption offset relative to the CO2 center frequency. The assignment of the rotovibrational states for the pump and the emission transitions of ethyl bromide are calculated. We also partly assigned the rotational levels of trioxane. 相似文献
54.
55.
Italo Carelli Mario Emilio Cardinali Franco Micheletti Moracci 《Journal of Electroanalytical Chemistry》1980,107(2):391-404
In aqueous media, 1-benzyl-3-carbamoylpyridinium ion undergoes an initially reversible one-electron reduction to produce a free radical, which irreversibly dimerises to a 4,4′-linked diastereoisomeric pair. At more negative potential, the free radical undergoes a further one-electron reduction to a mixture of 1,6- and 1,4-dihydropyridine derivatives. At sufficiently positive potential the dimers can be oxidised back to pyridinium cation. The dimeric products are strongly adsorbed on the electrode surface, also at potential values where 2e products are formed, and this is a preparative drawback for the dimers and the dihydropyridines. Such problems can be overcome by the addition of benzene and of surface-active substances respectively. A detailed mechanism of the electrochemical reduction of 1-benzyl-3-carbamoylpridinium ion is proposed. 相似文献
56.
Manzoni L Arosio D Belvisi L Bracci A Colombo M Invernizzi D Scolastico C 《The Journal of organic chemistry》2005,70(10):4124-4132
[reaction: see text] An efficient and operationally simple method for the synthesis of functionalized azaoxobicyclo[X.3.0]alkane amino acids has been devised. The key step is an intramolecular nitrone cycloaddition on 5-allyl- or 5-homoallylproline that was found to be completely regio- and stereoselective. 相似文献
57.
58.
Bertolini A Carelli G Francesconi F Francesconi M Marchesini L Marsili P Sorrentino F Cristoforetti G Legnaioli S Palleschi V Pardini L Salvetti A 《Analytical and bioanalytical chemistry》2006,385(2):240-247
Laser-induced breakdown spectroscopy (LIBS) is a promising technique for in situ elemental analysis. A new mobile instrument
for LIBS analysis, developed in a collaboration between Marwan Technology s.r.l. and the Applied Laser Spectroscopy Laboratory
in Pisa, is presented, and some applications of it and results from it are outlined. The innovative experimental set-up, based
on the use of two suitably retarded laser pulses and a standardless analysis procedure, which overcomes problems related to
matrix effects, greatly improves the potential of this technique for accurate quantitative analysis.
相似文献
59.
Considered as a geophysical fluid, the polluted atmosphere shares the shallow domain characteristics with other natural large-scale fluids such as seas and oceans. This means that its domain is excessively greater horizontally than in the vertical dimension, leading to the classic hydrostatic approximation of the Navier–Stokes equations. In the past there has been proved a convergence theorem for this model with respect to the ocean, without considering pollution effects. The novelty of this present work is to provide a generalization of their result translated to the atmosphere, extending the fluid velocity equations with an additional convection–diffusion equation representing pollutants in the atmosphere. 相似文献
60.
We describe the behavior of p-harmonic Green’s functions near a singularity in metric measure spaces equipped with a doubling measure and supporting a
Poincaré inequality. 相似文献