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121.
The Nemitskii operator in the Hölder spaces C0, () with an open bounded subset of Rn, is studied; necessary and sufficientconditions are given for boundedness, uniform continuity, anduniformly continuous differentiability on bounded sets. 相似文献
122.
Giuseppe Arena Raffaele P. Bonomo Annalinda Contino Fabio G. Gulino Antonio Magrì Domenico Sciotto 《Journal of inclusion phenomena and macrocyclic chemistry》1997,29(3-4):347-363
A new water soluble receptor 5,11,17,23-tetrasulphonato-25,27-di(hydroxycarbonylmethoxy)-26,28-dihydroxycalix[4]arene was synthesized andcharacterized and its proton and copper(II) complexes were studied andcompared with the analogous species of the fully carboxylated ligand5,11,17,23-tetrasulphonato-25,26,27,28-tetrakis(hydroxycarbonylmethoxy)calix[4]arene. H° and S° values are crucial for understanding thepeculiar acid-base properties of the ligand. EPR spectra together with theUV-VIS spectral data reveal the coordination stereochemistry of thecopper(II) species. 相似文献
123.
Raffaele Esposito Antonio Romano 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1984,35(4):460-469
A mathematical formulation of the Gibbs variational principle is supplied for the equilibrium of a system of to fluids with an interface adsorbing or not and permeable or not. These properties of the interface are represented by suitable constraints for the admissible variations.
Work partially supported by G.N.F.M. of the Italian C.N.R. 相似文献
Sunto Viene fornita una rigorosa formulazione del principio variazionale di Gibbs per l'equilibrio di un sistema di due fluidi con un'interfaccia assorbente o non ed impermeabile o non. Dette proprietà dell'interfaccia sono tradotte da opportuni vincoli per le variazioni ammissibili.
Work partially supported by G.N.F.M. of the Italian C.N.R. 相似文献
124.
Antonio Laganà Osvaldo Gervasi Ranieri Baragli Domenico Laforenza Raffaele Perego 《Theoretical chemistry accounts》1993,84(4-5):413-421
Summary The apparently embarrassingly parallel problem of calculating a batch of quasiclassical trajectories to evaluate cross sections or rate constants has been analyzed. The study shows that only an accurate evaluation of the performance parameters and a consequent appropriate restructuring of the computer code allows the achievement of high speedup and efficiency especially when large calculations are implemented on massively parallel systems. 相似文献
125.
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
126.
Nevenka Bresciani-Pahor Giorgio Nardin Raffaele P. Bonomo Roberto Purrello 《Transition Metal Chemistry》1985,10(8):316-318
Conclusion The x-ray structural results confirm what has been ascertained by thermodynamic and spectroscopic data in aqueous solution(7). It is evident that the addition of pyridine to the solution containing the mixed species [Cu(bipy)(pydca)(H2O)] leads to the substitution of a water molecule directly bound to copper(II) ion by a pyridine molecule. This experiment also demonstrated the presence of a water molecule in the equatorial plane of the complex.The subsequent diffractometric study on single crystals derived from the copper(II)/bipy/pydca system revealed the existence in the solid state of [Cu2(bipy)2(pydca)2] · 4H2O. Thus the pydca dianion, instead of forming the statistically favoured mixed complex [Cu(bipy)(pydca)], gives rise to crystals containing two different copper(II) environments: [Cu(pydca)2]2– and [Cu(bipy)2]2+, linked by O-carboxylate bridges. The facility with which [Cu(bipy)(pydca)(py)] can be obtained shows that the addition of pyridine prevents the formation of polynuclear species. 相似文献
127.
The solvation free energy ΔGsol of molecules exhibiting the anomeric effect is computed in an approach that considers a continuous distribution for the solvent. A partition of ΔGsol into separately evaluated contributions confirms that changes in the energy of the systems due to changes in conformation of the solute are ruled by the electrostatic contribution. A comparison with the “exact” values indicates that the approximate expression for the electrostatic contribution to ΔGsol are not accurate enough to permit a proper modeling of the solvent influence on the anomeric effect. The systems are composed of methanediol, methoxymethanol, dimethoxymethane, and 2-methoxytetrahydropyran in carbon tetrachloride, chloroform, acetone, and water. The calculations have been performed at the SCF level with the STO -3G and 4–31G basis sets. 相似文献
128.
N-Boc derivatives of Met, Cys, and Trp, the properties of which resemble those of the respective amino acid residues present in proteins, are efficiently oxidized by methyltrioxorhenium and H2O2. A high regioselectivity for the oxidation of these residues when embedded into peptides was also found. 相似文献
129.
130.