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1.
Daniele Di Gioacchino Augusto Marcelli Antonio Bianconi 《Journal of Physics and Chemistry of Solids》2010,71(8):1046-1052
In this contribution we present the analysis of the third harmonic susceptibility data of the new superconductor NdFeAs1−0.14F0.14. ‘Cole-Cole’ polar plots respect to the magnetic frequency of the exciting field are presented and discussed. Data show that NdFeAs1−0.14F0.14 exhibit a ‘bulk pinning’ with a 3D flux dynamic character. A comparison of the responses of high Tc materials and an evaluation of theoretical critical states is also presented. 相似文献
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Meccanica - This work deals with viscoelastic constitutive models involving variable-order fractional operators. There exist two main fractional models in the literature representing the... 相似文献
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Meccanica - The research of a formulation to model non-local interactions in the mechanical behavior of matter is currently an open problem. In this context, a strong non-local formulation based on... 相似文献
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Gioacchino Viggiani Nicolas Lenoir Pierre Bésuelle Marco Di Michiel Stefania Marello Jacques Desrues Mogens Kretzschmer 《Comptes Rendus Mecanique》2004,332(10):819-826
This Note presents a few selected results of an experimental testing program carried out at the ESRF in Grenoble, France. X-ray microtomography (with a spatial resolution of 14 μm) has been used to evaluate the onset and evolution of shear banding in a fine-grained stiff soil under deviatoric loading. It allowed detailed observations of strain localization in a specimen during the test, including the presence of more than one shear zone and a varying degree of dilatancy and/or crack opening. To cite this article: G. Viggiani et al., C. R. Mecanique 332 (2004). 相似文献
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Loreti V Toncelli D Morelli E Scarano G Bettmer J 《Analytical and bioanalytical chemistry》2005,383(3):398-403
Cd-bound phytochelatins (Cd–PCs) have been synthesised by incubation of Phaeodactylum tricornutum cell cultures with Cd and purified by size-exclusion chromatography–UV–Vis. These complexes, which were identified in previous
work, have now been used as model substances to develop and optimise ion-pair chromatography (IPC) coupled to inductively
coupled plasma–mass spectrometry (ICP–MS) for analysis of Cd–PCs. Subsequent analysis of samples taken from Silene vulgaris plants cultivated under heavy metal stress conditions revealed Cd signals but no Cd–PC signals. By use of isotopically enriched
116Cd–PCs the sample preparation steps were verified to determine the stability of the analytes. We observed species transformation
between Cd–PCs and other unidentified Cd complexes. Consequently, the kinetic and thermodynamic lability of Cd–PCs are decisive
factors in their detection. 相似文献
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Gianluca A. Mannella Francesco Carfì Pavia Gioacchino Conoscenti Vincenzo La Carrubba Valerio Brucato 《Journal of Polymer Science.Polymer Physics》2014,52(14):979-983
Thermally induced phase separation is a fabrication technique for porous polymeric structures. By means of easy‐to‐tune processing parameters, such as system composition and demixing temperature, a vast latitude of average pore dimensions, pore size distributions, and morphologies can be obtained. The relation between demixing temperature and morphology was demonstrated via cloud point curve measurement and foams fabrication with controlled thermal protocols, for the model system poly‐l ‐lactide–dioxane–water. The morphologies obtained at a temperature lower than cloud point showed a closed‐pore architecture, suggesting a “nucleation‐and‐growth” separation mechanism, which produced larger pores at higher holding times. Conversely, the porous structures attained when holding the sample above the cloud point exhibited open pores with dimensions independent of time, denoting a phase separation occurring during sample freezing. Finally, the influence of the cooling rate on final morphology was investigated, showing a clear correlation with microstructure and pore size. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 979–983 相似文献
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Serra A Siciliano T Filippo E Micocci G Tepore A Arnold DP Valli L 《Langmuir : the ACS journal of surfaces and colloids》2005,21(1):294-298
Langmuir-Blodgett films containing meso,meso'-buta-1,3-diyne-bridge Cu(II) octaethylporphyrin dimer have been deposited with the aim of carrying out a thermally stimulated current (TSC) investigation. This characterization was obtained upon cooling samples irradiated by light and others without irradiation: in this way TSC curves have been registered in the temperature range of 100-300 K. Analysis of experimental data has been performed through the application of three different approaches: the initial rate, the heating rate, and Chen's methods. In particular, a trap center at about 0.38 eV has been evidenced and the three different methods have given results in close accordance. 相似文献
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Michael Di Gioacchino Fabio Bruni Armida Sodo Silvia Imberti 《Molecular physics》2019,117(22):3311-3319
Neutron diffraction with isotopic H/D substitution on water, augmented by Empirical Potential Structure Refinement has been applied to extract the hydration properties of the osmolyte zwitterionic ectoine at 1.5?M concentration. This has evidenced differences between the hydration of COO? and NH groups, both in terms of number of water molecules involved in the hydration shell and of three-dimensional symmetry. Signatures of ectoine–ectoine contacts, due to hydrogen bonds, have been found, as possible precursors of ectoine aggregation at higher concentrations. The influence of ectoine on the water structure is ascribed to the dipolar electric field generated by the exposed charges of ectoine. 相似文献
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In this paper a three-dimensional isotropic fractional viscoelastic model is examined. It is shown that if different time scales for the volumetric and deviatoric components are assumed, the Poisson ratio is time varying function; in particular viscoelastic Poisson ratio may be obtained both increasing and decreasing with time. Moreover, it is shown that, from a theoretical point of view, one-dimensional fractional constitutive laws for normal stress and strain components are not correct to fit uniaxial experimental test, unless the time scale of deviatoric and volumetric are equal. Finally, the model is proved to satisfy correspondence principles also for the viscoelastic Poisson’s ratio and some issues about thermodynamic consistency of the model are addressed. 相似文献