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Inventories and price changes are correlated. The inverse relation is most obvious in housing where inventories build in low-demand markets and shrink in high-demand markets. This is a puzzle. Symmetry of information among buyers and sellers would seem to imply that sellers would change their reservation value by the amount that buyers change their offers. Because there is heterogeneity among buyers in the valuation of a given house, sellers set prices strategically. When demand falls, sellers rationally lower their prices, but not by enough to keep the probability of sale constant. As a result, inventories grow.

The dependencies of the melting point and the lattice parameter of supported metal nanoclusters as functions of clusters height are theoretically investigated in the framework of the uniform approach. The vacancy mechanism describing the melting point and the lattice parameter shifts in nanoclusters with decrease in their sizes is proposed. It is shown that under the high vacuum conditions (p < 10^-7torr) the essential role in clusters melting point and lattice parameter shifts is played by van der Waals forces of cluster–substrate interaction. The proposed model satisfactorily accounts for the experimental data.

We investigate the effects of vacancies, disorder and sublattice polarization on the electronic properties of a monolayer graphene in the quantum Hall regime. Energy spectra as a function of magnetic field and the localization properties of the states within the graphene Landau levels (LLs) are calculated through a tight-binding model. We first discuss our results considering vacancies in the lattice, where we show that vacancies introduce extra levels (or well-defined bands) between consecutive LLs. An striking consequence here is that extra Hall resistance plateaus are expected to emerge when an organized vacancy superlattice is considered. Secondly, we discuss the anomalous localization properties we have found for the lowest LL, where an increasing disorder is shown to enhance the wave functions delocalization (instead of inducing localization). This unexpected effect is shown to be directly related to the way disorder increasingly destroys the sublattice (valley) polarization of the states in the lowest LL. The reason why this anomalous disorder effect occurs only for the zero-energy LL is that, in absence of disorder, only for this level all the states are sublattice polarized, i.e., their wave functions have amplitudes in only one of the sublattices.

Density functional theory and generalized gradient approximation have been employed to study Mg, Si and O vacancies in the Mg₂SiO₄ forsterite mineral. Microstructure of defect equilibrium geometries, electronic properties as well as chemical bonding in the region surrounding each one of the vacancies have been computed and discussed in detail. It is found that vacancies tend to increase covalent character of the chemical bonding for atoms situated in their vicinity independently of the type of vacancy. Nevertheless, obtained atomic distortion in the region surrounding vacancies generally obeys Coulomb electrostatic interaction law. Local energy states are found in the band-gap region due to the occurrence of vacancy-type defects. These findings are discussed in light of the available experimental data.

The influence of periodic edge vacancies and antidot arrays on the thermoelectric properties of zigzag graphene nanoribbons (ZGNRs) are investigated. Using Green’s function method, the tight-binding approximation for the electron Hamiltonian and the 4th nearest neighbor approximation for the phonon dynamical matrix, we calculate the Seebeck coefficient and the thermoelectric figure of merit. It is found that, at a certain periodic arrangement of vacancies on both edges of zigzag nanoribbon, a finite band gap opens and almost twofold degenerate energy levels appear. As a result, a marked increase in the Seebeck coefficient takes place. It is shown that an additional enhancement of the thermoelectric figure of merit can be achieved by a combination of periodic edge defects with an antidot array.

Sr_0.6Na_0.2Nd_0.2Bi₄Ti₄O₁₅ ceramic is prepared by mixed oxide method. Lattice parameters for this ceramic are calculated from the X-ray diffraction data. Dielectric studies as a function of temperature and frequency are done. To understand the process of conduction involved in the material prepared, frequency and temperature dependency of AC conductivity studies are carried out. The two-term power relation is used to characterize the frequency dependence of AC conductivity. The parameters s₁, s₂ (low and high frequency slopes) are calculated from the AC conductivity plots at different temperatures to get more information about the conduction mechanism. Conduction is explained based on hopping mechanism occuring via polarons.