Spatial interaction in magneto-micropolar continua

Summary We consider a micropolar continuum, whose material points are endowed with magnetic moment, in the presence of a magnetic field within the approximation of the quasimagnetostatics. We deduce the balance equations by a suitable averaging technique and then we examine the compatibility of spatial interaction effects with thermodynamics. As a result, we show that such effects are confined to the constitutive equations for the dissipative stress_DT, the dissipative couple stress_Dm and the heat flux q. Moreover, as a consequence of the reduced dissipation inequality, a linear theory would account only for a dependence of_DT,_Dm, and q on the velocity gradient, the angular velocity, the gradient of the angular velocity, and on the temperature gradient.

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Sommario Si considera un continuo micropolarc, i cui punti materiali sono dotati di momento magnetico, in presenza di un campo magnetico nell'approssimazione della quasimagnetostatica. Dopo aver dedotto le equazioni di bilancio mediante un opportuno procedimento di media, si esamina la compatibilità tra effetti di interazione spaziale e seconda legge della termodinamica e si mostra che tali effetti possono essere presenti solo nelle equazioni costitutive per lo stress dissipativo (di Cauchy)_DT.lo stress dissipativo delle coppie_Dm e il flusso di calore q. Inoltre, in conseguenza della disuguaglianza di dissipazione ridotta, si osserva che una teoria lineare permetterebbe solo una dipendenza di_DT,_Dm, q dal gradiente di velocità, dalla velocità angolare, dal gradiente della velocità angolare e dal gradiente di temperatura.

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This work was supported by the «Gruppo Nazionale per la Fisica Matematica» of CNR.     

Solid phase synthesis of a molecular library of pyrimidines, pyrazoles, and isoxazoles with biological potential

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Parametric, external and self-excitation of a tower under turbulent wind flow

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Large tunable Rashba spin splitting of a two-dimensional electron gas in Bi2Se3

We report a Rashba spin splitting of a two-dimensional electron gas in the topological insulator Bi(2)Se(3) from angle-resolved photoemission spectroscopy. We further demonstrate its electrostatic control, and show that spin splittings can be achieved which are at least an order-of-magnitude larger than in other semiconductors. Together these results show promise for the miniaturization of spintronic devices to the nanoscale and their operation at room temperature.     

Simultaneous quantization of bulk conduction and valence states through adsorption of nonmagnetic impurities on Bi2Se3

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Synthesis and characterization of silicon-doped gallium oxide nanowires for optoelectronic UV applications

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Magnetic field induced orbital polarization in cubic YbInNi4: determining the quartet ground state using x-ray linear dichroism

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Fast perturbation Monte Carlo method for photon migration in heterogeneous turbid media

We present a two-step Monte Carlo (MC) method that is used to solve the radiative transfer equation in heterogeneous turbid media. The method exploits the one-to-one correspondence between the seed value of a random number generator and the sequence of random numbers. In the first step, a full MC simulation is run for the initial distribution of the optical properties and the "good" seeds (the ones leading to detected photons) are stored in an array. In the second step, we run a new MC simulation with only the good seeds stored in the first step, i.e., we propagate only detected photons. The effect of a change in the optical properties is calculated in a short time by using two scaling relationships. By this method we can increase the speed of a simulation up to a factor of 1300 in typical situations found in near-IR tissue spectroscopy and diffuse optical tomography, with a minimal requirement for hard disk space. Potential applications of this method for imaging of turbid media and the inverse problem are discussed.     

Configuration interactions constrained by energy density functionals

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Can long-run dynamic optimal strategies outperform fixed-mix portfolios? Evidence from multiple data sets

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