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991.
Ágnes Keszler Károly Héberger Dezs Gál Livius Cotarca Pietro Delogu 《Reaction Kinetics and Catalysis Letters》1994,53(2):385-390
A mechanism is suggested for the oxidative decarboxylation of cyclohexane monocarboxylic acid initiated by decomposition of H2O2. The process is a non-branching chain reaction. Cyclohexanone and cyclohexanol form in termination reactions. 相似文献
992.
Cucinotta F Di Pietro ML Puntoriero F Giannetto A Campagna S Cusumano M 《Dalton transactions (Cambridge, England : 2003)》2008,(35):4762-4769
The luminescence properties of eleven Pt(ii) complexes containing polypyridine ligands with extended aromatic moieties have been studied, both in acetonitrile fluid solution at 298 K and in butyronitrile rigid matrix at 77 K. For comparison purposes, also the phosphorescence properties of three free ligands at 77 K in butyronitrile have been investigated. The absorption spectra of all the compounds exhibit intense bands (epsilon in the range 10(4)-10(5) M(-1) cm(-1)) in the UV region, which are attributed to spin-allowed ligand-centered (LC) transitions, and moderately intense bands (epsilon in the range 10(3)-10(4) M(-1) cm(-1)) in the visible region, which receive contribution from both spin-allowed LC transitions and spin-allowed metal-to-ligand charge-transfer (MLCT) transitions. At low energy, less intense spin-forbidden MLCT bands are also present. At 77 K in rigid matrix, all the studied compounds exhibit structured and long-lived (lifetimes from 840 mus on the millisecond timescale) luminescence, which is attributed to triplet LC states in all cases. At room temperature in fluid solution the luminescence lifetime of all the compounds is largely shortened (nanosecond timescale), and most of the emission spectra are unstructured and red-shifted. For species exhibiting structured emission spectra even at room temperature, low luminescence quantum yields are always obtained (Phi < 10(4)), and their emission is assigned to triplet LC states, which mainly deactivate to the ground state by thermal-activated surface crossing to a closely-lying metal-centered (MC) triplet state. Compounds exhibiting unstructured emission show relatively high emission quantum yields (about 0.1) and their emission is assigned to a mixed LC/MLCT state. 相似文献
993.
Cristina Forzato Giada Furlan Patrizia Nitti Giuliana Pitacco Ennio Valentin Ennio Zangrando Pietro Buzzini Marta Goretti Benedetta Turchetti 《Tetrahedron: Asymmetry》2008,19(17):2026-2036
The synthesis of γ-phenyl and γ-(n-pyridyl)paraconates was accomplished by chemical reduction of their respective ketodiester precursors followed by cyclisation of the resulting hydroxy diester intermediates. The cis- and trans-lactones thus obtained were separated and separately subjected to enzymatic hydrolysis with HLAP. The cis-lactonic esters had enantiomeric excesses ranging from 94% to 99%, while for the trans-isomers the ee’s ranged from 80% to 93%. The same ketodiester precursors were subjected to reduction with a series of yeasts. The absolute configuration of trans-(−)-2-pyridyl paraconic acid was assigned by means of X-ray analysis of its hydrobromide salt, while the absolute configurations of the other lactones were determined via analysis of their respective CD curves. 相似文献
994.
995.
996.
997.
Pietro D'Ambrosio Domenico De Tommasi Pilade Foti Mario Daniele Piccioni 《Journal of Elasticity》2003,73(1-3):237-249
In this paper we obtain necessary conditions for the existence of pairwise deformations of an incompressible, isotropic elastic body subjected to a homogeneous distribution of dead-load tractions. Explicit restrictions on the boundary loads and on the surface of discontinuity between the phases are determined. For hyperelastic bodies with stored energy depending only on the first invariant of strain, we show that pairwise deformations under examination are necessarily (within a rigid rotation) plane deformations. 相似文献
998.
999.
D. Pierroutsakou A. Boiano A. De Rosa M. Di Pietro G. Inglima M. La Commara Ruhan Ming B. Martin R. Mordente A. Ordine F. Rizzo V. Roca M. Romoli M. Sandoli F. Soramel L. Stroe M. Trotta E. Vardaci 《The European Physical Journal A - Hadrons and Nuclei》2003,17(1):71-76
The 32S + 100Mo and 36S + 96Mo fusionlike reactions were studied at incident energy of E
lab = 298 MeV and 320 MeV, respectively, with the aim of probing the influence of the entrance channel charge asymmetry on the
dipole γ-ray emission. The excitation energy and spin distribution of the compound nucleus created in these reactions were
identical, the only difference being associated with the unequal charge asymmetry of the two entrance channels. High-energy
γ-rays were detected in an array of 9 seven-pack BaF2 clusters. Coincidence with fusionlike residues detected in four PPAC ensured the selection of central reaction events. By
studying the differential γ-ray multiplicity associated with the two reactions it was shown that the dipole strength excited
in the compound nucleus increases with the entrance channel charge asymmetry. From the linearized spectra, the increase of
the GDR γ-ray intensity was found to be ∼ 25% for the more charge asymmetric system. The results are discussed and compared
with those of previous data obtained at different incident energies.
Received: 21 October 2002 / Accepted: 23 December 2002 / Published online: 1 April 2003 相似文献
1000.
Anatolii Baskakov Pietro Zecca 《Journal of Mathematical Analysis and Applications》2006,324(2):1310-1323
In this paper we study the solvability of some classes of differential inclusions with multivalued linear operators in homogeneous spaces of functions. These spaces include a large number of functional spaces like periodic functions and Bohr and Stepanov almost periodic functions. As an application, we consider some existence results for feedback control systems governed by degenerate differential equations of Sobolev type in a Banach space. 相似文献