The bulk thermal rectifiers usable at a high temperature above 300 K were developed by making full use of the unusual electron thermal conductivity of icosahedral quasicrystals. The unusual electron thermal conductivity was caused by a synergy effect of quasiperiodicity and by a narrow pseudogap at the Fermi level. The rectification ratio, defined by TRR = [Formula: see text], reached vary larg...

The quantum magnetic oscillations of electrical sShubnikov–de Haas effectd and thermal conductivities are studied for graphene which represents a distinctive example of planar systems with a linear, Dirac-like spectrum of quasiparticle excitations. We show that if utmost care is taken to separate electron and phonon contributions in the thermal conductivity, the oscillations of electron thermal...

Conductivity of a disorder-free intrinsic graphene is studied to the first order in the long-range Coulomb interaction and is found to be σ = σ0(1+0.01g), where g is the dimensionless (“fine structure”) coupling constant. The calculations are performed using three different methods: i) electron polarization function, ii) Kubo formula for the conductivity, iii) quantum transport equation. Surpri...

We study the frequency-dependent conductivity of a nondegenerate two-dimensional electron system (2DES) in a quantizing magnetic field in the presence of weak short-range disorder. The 2DES is correlated, forming a liquid, which makes it necessary to account for electron–electron interaction (EEI) nonperturbatively. In strong magnetic fields, the low-frequency conductivity can be expressed pert...

In this paper, we investigated the statistical analysis of thermal conductivity of nanofluids containing of decorated Ag nanorods with Cu nanoparticles. For this purpose Ag-Cu hybrid is synthesized and characterized using transmission electron microscopy (TEM) and X-ray diffraction pattern (XRD). TEM image shows that Cu nanoparticles successfully decorate on the outer surface of Ag nanorods. Th...

A physically-based model for the electrical conductivity of peak aged and overaged Al-Zn-Mg-Cu (7xxx series) alloys is presented. The model includes calculations of the η and the S phase solvus (using a regular solution model), taking account of the capillary effect and η coarsening. It takes account of the conductivity of grains (incorporating dissolved alloying elements, undissolved particles...

We investigate the minimum conductivity of graphene within a quasiclassical approach taking into account electron-hole coherence effects which stem from the chiral nature of low energy excitations. Relying on an analytical solution of the kinetic equation in the electron-hole coherent and incoherent cases, we study both the electrical and the thermal conductivity whose relation satisfies the Wi...

This paper reports a modeling study of the modifications of the nighttime lower ionospheric conductivity by electrostatic fields produced by underlying thunderstorms. The model used combines Ohm’s law with a simplified lower ionospheric ion chemistry model to self-consistently calculate the steady state nighttime conductivity above a thunderstorm. The results indicate that although the electron...

Previously, we considered the analytical solution of nonlinear diffusion equation in two-dimensional surface. This allows us to consider the same nonlinear heat conduction equation for metals heated by a picosecond laser. After fast thermalization (within a few femtoseconds) of the laser energy and electron excitation in the conductivity band, electrons ballistically diffuse and transfer their ...

nanofber  mats  of  poly(ε-caprolactone)/nanoclay  nanocomposites  were fabricated by electrospinning. the effects of the solution concentration and  the  nanoclay  content  of  nanocomposite  materials  on  the  fnal nanofber  structure were  investigated. morphology  and  diameter  of  the  nanofbers were studied using optical and scanning electron microscope. it was observed that the  poly(ε...