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91.
Bordiga S Vitillo JG Ricchiardi G Regli L Cocina D Zecchina A Arstad B Bjørgen M Hafizovic J Lillerud KP 《The journal of physical chemistry. B》2005,109(39):18237-18242
Hydrogen storage is among the most demanding challenges in the hydrogen-based energy cycle. One proposed strategy for hydrogen storage is based on physisorption on high surface area solids such as metal-organic frameworks (MOFs). Within this class of materials, MOF-5 has been the first structure studied for hydrogen storage. The IR spectroscopy of adsorbed H2 performed at 15 K and ab initio calculations show that the adsorptive properties of this material are mainly due to dispersive interactions with the internal wall structure and to weak electrostatic forces associated with O13Zn4 clusters. Calculated and measured binding enthalpies are between 2.26 and 3.5 kJ/mol, in agreement with the H2 rotational barriers reported in the literature. A minority of binding sites with higher adsorption enthalpy (7.4 kJ/mol) is also observed. These species are probably associated with OH groups on the external surfaces present as termini of the microcrystals. 相似文献
92.
Andrea Donato 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1976,27(2):281-284
Summary We reduce the magneto-thermo-elastic system with one-dimensional deformation to the Burgers' equation which describes the shocks when dissipative terms occur.
Work supported by the C.N.R. through the Gruppo Nazionale per la Fisica-matematica. 相似文献
Sommario Applicando un metodo pertubativo di Taniuti e Wei si riduce il sistema della magneto-termoelasticità con deformazioni unidimensionali all'equazione di Burgers che descrive gli urti in presenza di termini dissipativi.
Work supported by the C.N.R. through the Gruppo Nazionale per la Fisica-matematica. 相似文献
93.
Raffaele Borrelli Mariangela Di Donato Andrea Peluso 《Theoretical chemistry accounts》2007,117(5-6):957-967
Mechanistic aspects of some of the early electron transfer steps occurring in photosynthetic reaction centers are discussed.
Starting from the normal modes of the redox cofactors involved in the electron transfer processes, we show how a series of
quantities which regulate electron transfer rates, such as (i) the electron transfer active modes, (ii) the intramolecular
reorganization energy, and (iii) the mutual couplings between the vibronic states of the donor and the acceptor, can be obtained
and used to draw qualitative conclusions on ET rates. 相似文献
94.
95.
Donato Pocar Pasqualina Trimarco Riccardo Destro Emanuele Ortoleva Marzia Ballabio 《Tetrahedron》1984,40(18):3579-3585
2,3-Diamino-1,3-butadienes (1) reacted with β-nitrostyiene or nitroethene to afford a mixture ofisomeric 1,5-diaminoo-5-methyl-4-nitro-cyclopentenes (3 and 4). The configuration of the main isomers (3) was established by X-ray diffraction analysis which also revealed the great steric crowding of this molecule. The conformation of the cyclopentene ring in 3 in the solid state is also discussed. The enamines (3 and 4) were hydrolyzed to the corresponding aminoketones (5 and 6) which, on reduction, gave the same diaminoketone (7). 相似文献
96.
The release of H2O2 by plant cell suspensions elicited with crude hyphal wall preparations has been studied in a complex of plant genotypes (two
cvs ofCapsicum annuum and one of C.frutescens) and fungus species(Phytophthora capsici, Ph. parasitica andVerticillium dahliae), representing several combinations of compatibility and both host and nonhost resistance. Production of H2O2 was revealed as peroxidasedependent and catalase-inhibited fluorescence quenching of an extracellular probe (Pyranine).
All the plant genotypes responded to at least one elicitor, but the cell sensitivity showed a great age-dependent variability.
Riboflavine and Mn2+ added in the incubation medium acted to some extent as primers for activated cell response, as well as a high Na+ concentration. Cell rest condition, however, was not removed. Some quantitative features of responsive plant/elicitor combinations
(dose-response relation and lasting time) have been recorded.
The complex PO/H2O2 of elicited cells could perform detectable lignin-like polymerization of an exogenous natural substrate (coniferyl alcohol).
The time-course of pyranine oxidation and lignin-like polymer formation could be recorded by adopting a fluorimetric procedure
that allowed sequential observations on the same cell sample. In one instance, the cell reaction seemed associated with thein planta host/parasite incompatibility. 相似文献
97.
Alvis Mengots Andreas Erbs Hillers-Bendtsen Dr. Sandra Doria Frederik Ørsted Kjeldal Nicolai Machholdt Høyer Dr. Anne Ugleholdt Petersen Prof. Dr. Kurt V. Mikkelsen Dr. Mariangela Di Donato Prof. Dr. Martina Cacciarini Prof. Dr. Mogens Brøndsted Nielsen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(48):12437-12446
Photoswitch triads comprising two dihydroazulene (DHA) units in conjugation with a central trans-azobenzene (AZB) unit were prepared in stepwise protocols starting from meta- and para-disubstituted azobenzenes. The para-connected triad had significantly altered optical properties and lacked the photoactivity of the separate photochromes. In contrast, for the meta-connected triad, all three photochromes could be photoisomerized to generate an isomer with two vinylheptafulvene (VHF) units and a cis-azobenzene unit. Ultrafast spectroscopy of the photoisomerizations revealed a fast DHA-to-VHF photoisomerization and a slower trans-to-cis AZB photoisomerization. This meta triad underwent thermal VHF-to-DHA back-conversion with a similar rate of all VHFs, independent of the identity of the neighboring units, and in parallel thermal cis-to-trans AZB conversion. The experimental observations were supported by computation (excitation spectra and orbital analysis of the transitions). 相似文献
98.
99.
Riccardo Molle Donato Passaseo 《Calculus of Variations and Partial Differential Equations》2006,26(2):201-225
The paper deals with the existence of positive solutions of the problem -Δ u=up in Ω, u=0 on ∂Ω, where Ω is a bounded domain of
, n≥ 3, and p>2. We describe new concentration phenomena, which arise as p→ +∞ and can be exploited in order to construct, for p large enough, positive solutions that concentrate, as p→ +∞, near submanifolds of codimension 2. In this paper we consider, in particular, domains with axial symmetry and obtain
positive solutions concentrating near (n-2)-dimensional spheres, which approach the boundary of Ω as p→ +∞. The existence and multiplicity results we state allow us to find positive solutions, for large p, also in domains which can be contractible and even arbitrarily close to starshaped domains (while no solution can exist
if Ω is starshaped and
, as a consequence of the Pohožaev's identity).
Mathematics Subject Classification (2000) 35J20, 35J60, 35J65 相似文献
100.
Maria Bernadette Donato Monica Milasi Antonio Villanacci 《Journal of Mathematical Analysis and Applications》2018,457(2):1353-1369
We deal with the analysis of the general equilibrium model with incomplete financial markets and nominal assets. We assume that there are 2 periods of time, say today and tomorrow. We define a consumption, portfolio holding, commodity and asset price vector as an equilibrium vector associated with a given economy if at those prices and economies households maximize utility under a budget constraints and markets clear. While the path breaking proofs of existence by Cass [6] and Werner [25] use a fixed point argument, we provide an independent existence proof in terms of variational inequalities (about the variational approach for the analysis of general equilibrium models see for example [9] and [10]). The analysis presented in this paper indicates that the variational inequality approach promises to be applicable in many specifications of the incomplete market model. 相似文献