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81.
Enzo Marinari Giorgio Parisi Federico Ricci-Tersenghi Juan J. Ruiz-Lorenzo Francesco Zuliani 《Journal of statistical physics》2000,98(5-6):973-1074
We discuss replica symmetry breaking (RSB) in spin glasses. We update work in this area, from both the analytical and numerical points of view. We give particular attention to the difficulties stressed by Newman and Stein concerning the problem of constructing pure states in spin glass systems. We mainly discuss what happens in finite-dimensional, realistic spin glasses. Together with a detailed review of some of the most important features, facts, data, and phenomena, we present some new theoretical ideas and numerical results. We discuss among others the basic idea of the RSB theory, correlation functions, interfaces, overlaps, pure states, random field, and the dynamical approach. We present new numerical results for the behaviors of coupled replicas and about the numerical verification of sum rules, and we review some of the available numerical results that we consider of larger importance (for example, the determination of the phase transition point, the correlation functions, the window overlaps, and the dynamical behavior of the system). 相似文献
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85.
Nadia Marchettini Rolando Barbucci Claudia Bonechi Alessandro Donati Agnese Magnani Valentina Niccolucci Enzo Tiezzi 《Macromolecular Symposia》1999,138(1):203-208
The hexasaccharide (trimer) and tetrasaccharide (dimer) oligomers of hyaluronic acid were investigated by 1H and 13C high resolution Nuclear Magnetic Resonance. The dynamic behavior of the molecules and their complexation with copper(II) were analysed by 1H NMR relaxation studies. A specific site for the complexation of the tetrasaccharide with Cu2+ was demonstrated by analysis of the paramagnetic effect of the metal on non-selective proton relaxation rates. A model for the complex involving two molecules of the tetrasaccharide is proposed. 相似文献
86.
G. Mulas S. Enzo C. Bonatto Minella E. Arca C. Gerbaldi N. Penazzi S. Bodoardo J. Hassoun S. Panero 《Journal of Solid State Electrochemistry》2009,13(2):239-243
We focus on the synthesis by ball milling and on the electrochemical characterization of nanocrystalline bimetallic and composite
materials to be employed as anodes in Li ion batteries. Ni3Sn4 and Ni3Sn2 based compounds were obtained by ball milling of three different Ni–Sn mixtures. The properties of the resulting anodes for
Li ion batteries were evaluated as a function of composition. Moreover, a biphasic system is presented, with CoSn2 and CoSn type structures, arising from the synthesis of the Sn31Co28C41 composition. When cycled in a Li cell, this material showed a high reversible specific capacity, about 450 mA h g−1, and a very good electrochemical and structural stability, making it of interest for application purposes.
Contribution to the Fall Meeting of the European Materials Research Society, Symposium D: 9th International Symposium on Electrochemical–Chemical
Reactivity of Metastable Materials, Warsaw, 17th–21st September, 2007. 相似文献
87.
Natural sediments show sequestering properties that can lead to a process of self-purification of aquatic environment from metal pollution. The study of the interaction between metal ions and sediment particles enhances what is known about the distribution and bioavailability of heavy metals in natural systems. Our contribution concerns the characterisation of the sequestering ability of a River Po sediment with regard to calcium(II), magnesium(II), cadmium(II), nickel(II) and copper(II), in fixed experimental conditions, through pH-metric and spectrometric measurements. A batch titration procedure was adopted and, in each solution, after equilibration, both pH and pM (M = Ca(II), Mg(II), Cd(II), Ni(II), Cu(II)) (via Inductively Coupled Plasma - Optical Emission Spectroscopy, ICP-OES) values were measured. The experimental data were first processed with a specific software to evaluate the concentration and protonation constants of the sediment ligand site(s). The speciation model was then assessed, together with the values of complexation constants, for the different sediment/metal cation systems. In order to better characterise the copper(II)-sediment interaction and to obtain more information about the nature of ligand site(s) involved, EPR (Electronic Paramagnetic Resonance) measurements were also made on the dry sediment before and after reaction with copper(II) ions. 相似文献
88.
Bruschi L Fois G Mistura G Tormen M Garbin V di Fabrizio E Gerardino A Natali M 《The Journal of chemical physics》2006,125(14):144709
We have measured the adsorption of argon films on arrays of microscopic nonlinear cusps and of semicircular channels. In the former case, we observe a distinct crossover from a planarlike to a geometry dependent growth behavior near liquid-vapor bulk coexistence, characterized by a growth exponent chi equal to -0.96+/-0.04 in very good agreement with the predictions of a recent scaling theory [C. Rascon and A. O. Parry, J. Chem. Phys. 112, 5175 (2000)]. The crossover location is also consistent with theory. Instead, on the concave channels we find a much steeper growth near saturation that may signal the formation of two menisci at both sides of the channel bottom. 相似文献
89.
Bratsos I Mitri E Ravalico F Zangrando E Gianferrara T Bergamo A Alessio E 《Dalton transactions (Cambridge, England : 2003)》2012,41(24):7358-7371
With the aim of expanding the structure-activity relationship investigation, the series of Ru(II) half sandwich coordination compounds of the type [Ru([9]aneS3)(chel)(L)](n+) previously described by us (where [9]aneS3 is the neutral face-capping ligand 1,4,7-trithiacyclononane, chel is a neutral or anonic chelating ligand, L = Cl(-) or dmso-S, n = 0-2) was extended to 1,4,7-triazacyclononane ([9]aneN3). In addition, new neutral N-N, and anionic N-O and O-O chelating ligands, i.e. dach (trans-1,2-diaminocyclohexane), pic(-) (picolinate), and acac(-) (acetylacetonate), were investigated in combination with both [9]aneS3 and [9]aneN3. Overall, ten new half-sandwich complexes were prepared and fully characterized and their chemical behaviour in aqueous solution was established. The single-crystal X-ray structures of eight of them, including the versatile precursor [Ru([9]aneN3)(dmso-S)(2)Cl]Cl (9), were also determined. The results of in vitro antiproliferative tests performed on selected compounds against MDA-MB-231 human mammary carcinoma cells confirmed that, in this series, only compounds that hydrolyse the monodentate ligand at a reasonable rate show moderate activity, provided that the chelate ligand is a hydrogen bond donor. 相似文献
90.
Kordatos Konstantinos Prato Maurizio Menna Enzo Scorrano Gianfranco Maggini Michele 《Journal of Sol-Gel Science and Technology》2001,22(3):237-244
We report on the synthesis of fullerene derivatives containing a trialkoxysilane moiety that exhibit enhanced solubility in solvents commonly used for sol-gel processing. These derivatives have been successfully embedded in glassy bulk samples and thin films that show very promising optical limiting properties. 相似文献