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Giovanna Bruni Vittorio Berbenni Franco Sartor Chiara Milanese Alessandro Girella Dionigio Franchi Amedeo Marini 《Journal of Thermal Analysis and Calorimetry》2012,108(1):235-241
In this work, thermoanalytical, diffractometry, and microscopy measurements have been performed in order to characterize the
effect of high energy milling on a drug active in the migraine prophylaxis and smoke cessation. We can assert that the mechanical
treatment induces only a partial amorphisation of the solid phase, in particular it reduces the crystal order by producing
lattice defects which propagate from the surface to the bulk crystal. For this reason, the DSC is able to detect the presence
of ordered solid, while the powder X-ray diffractometry, because of its low penetration depth, does not reach the crystalline
core of the particles. 相似文献
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Maria Luisa Dalla Chiara Roberto Giuntini Antonio Ledda Roberto Leporini Giuseppe Sergioli 《Foundations of Physics》2010,40(9-10):1494-1518
The characteristic holistic features of the quantum theoretic formalism and the intriguing notion of entanglement can be applied to a field that is far from microphysics: logical semantics. Quantum computational logics are new forms of quantum logic that have been suggested by the theory of quantum logical gates in quantum computation. In the standard semantics of these logics, sentences denote quantum information quantities: systems of qubits (quregisters) or, more generally, mixtures of quregisters (qumixes), while logical connectives are interpreted as special quantum logical gates (which have a characteristic reversible and dynamic behavior). In this framework, states of knowledge may be entangled, in such a way that our information about the whole determines our information about the parts; and the procedure cannot be, generally, inverted. In spite of its appealing properties, the standard version of the quantum computational semantics is strongly “Hilbert-space dependent”. This certainly represents a shortcoming for all applications, where real and complex numbers do not generally play any significant role (as happens, for instance, in the case of natural and of artistic languages). We propose an abstract version of quantum computational semantics, where abstract qumixes, quregisters and registers are identified with some special objects (not necessarily living in a Hilbert space), while gates are reversible functions that transform qumixes into qumixes. In this framework, one can give an abstract definition of the notions of superposition and of entangled pieces of information, quite independently of any numerical values. We investigate three different forms of abstract holistic quantum computational logic. 相似文献
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The title reaction was studied in different water–cosolvent (methanol) mixtures. The results have been rationalized employing the Marcus–Hush treatment. To apply this treatment, the true, unimolecular, electron‐transfer rate constants (ket) were obtained from the experimentally measured rate constants after calculation of the equilibrium constant for the processes of formation of the encounter complex. This calculation was carried out using Eigen–Fuoss (EF) and exponential mean spherical (EMSA) approaches employing effective values of the solvent dielectric constant. These effective values were obtained from the measured association constants corresponding to other ion pairs. The results reveal that in these media there is an additional component of reorganization energy, absent in neat solvents. An explanation of the origin of this component is given. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 41: 658–666, 2009 相似文献
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A. Andreone A. Di Chiara G. Peluso U. Scotti di Uccio F. Tafuri A. Barone G. Pepe F. Fontana 《Il Nuovo Cimento D》1990,12(6):863-868
Summary Some of the main anomalies in conductance characteristics of high-T
C tunnel junctions are considered. Mainly, the extreme, depression of gap structures, the presence of conductance peaks in
corrispondence to the counterelectrode gap, and ?zero-bias anomalies? will be examined. The possibility of application of
the proximity McMillan model to describe the behaviour in conductance of high-T
C junctions is considered. Discussion and preliminary comparison with experimental data on YBCO junctions are also reported. 相似文献