Electron-phonon interaction in the solid form of the smallest fullerene C20_{20}

The electron-phonon coupling of a theoretically devised carbon phase made by assembling the smallest fullerenes C$_{20}$ is calculated from first principles. The structure consists of C$_{20}$ cages in an {\it fcc} lattice interlinked by two bridging carbon atoms in the interstitial tetrahedral sites ({\it fcc}-C$_{22}$). The crystal is insulating but can be made metallic by doping with interstitial alkali atoms. In the compound NaC$_{22}$ the calculated coupling constant $\lambda/N(0)$ is 0.28 eV, a value much larger than in C$_{60}$, as expected from the larger curvature of C$_{20}$. On the basis of the McMillan's formula, the calculated $\lambda$=1.12 and a $\mu^*$ assumed in the range 0.3-0.1 a superconducting T$_c$ in the range 15-55 K is predicted.Comment: 7 page

Suppression of inelastic bound state resonance effects by the dimensionality of atom-surface scattering event

We develop a multidimensional coupled channel method suitable for studying the interplay of bound state resonance and phonon assisted scattering of inert gas atoms from solid surfaces in one, two and three dimensions. This enables us to get insight into the features that depend on the dimensionality of inelastic resonant processes typically encountered in low energy He atom scattering from surfaces, in general, and to elaborate on the observability of recently conjectured near threshold resonances in scattering from Einstein phonons, in particular.Comment: 2 figure

Responsible Management in the Framework of Market Economy

Background . It is more and more evident that long-term sustainable management cannot be carried out based only on financial data. Corporations operating in a market economy environment do not only aim at profit maximization as they have already realized that the ir performance depends on the sustainability of the environment and society. Financial motivations are the engine of corporate management, however, corporations c an still serve common wealth. Capitalism offers ever so many possibilities, opportunities f or corporations to be socially responsible. Research aim . This study was carried out to examine the CSR attitudes and commitments of the management of a corporation operating in the capitalist environment as well as to study their exact CSR practices. Method . The research is based on the questionnaire carried out among domestically and internationally owned SMEs in Hungary. The so-called snowball sample method was u sed. Key findings. The study attempts to find and reveal the reasons for the gap between the manager attitude and CSR practice based on the VoC

Estimation of the Poisson’s Rate of the Intact Rock in the Function of the Rigidity

Although Poisson’s ratio is one of the basic rock mechanical parameters, it is less investigated than the other parameters. It can be assumed, that this material constant depends on the rigidity of the rock, among the others. The goal of this research is to find a theoretical relationship between the rigidity of the intact rock and Poisson’s ratio. It was assumed that there is a connection between the internal friction angle (or cohesion) and rigidity of the isotropic, linear elastic material, using the Mohr-Coulomb theory. Based on these equations from different published limit equilibrium, six different equations were compared. It is published that the rigidity value is equal (within the experimental error) to the Hoek-Brown material constant (mi) which value is well-known for many different rock types. Plotting the published Poisson’s ratio in the function of the rigidity of the intact rock the optimal connection was chosen

Theoretical Relationship between the Confining Pressure and Poisson’s Ratio of Intact Rock

The Poisson’s ratio of the intact rock material is one of the basic material constants for rock engineering calculations in and on rock environments. Recently, several relationships were developed to calculate of the Poisson’s ratio of the intact rock from different mechanical parameters (e.g., rigidity index, cohesion, internal friction angle). This value can be measured under standardized laboratory conditions using traditional uniaxial compressive test at zero confining pressure. Analyzing the laboratory tests carried out at different confining pressure, it was found that this material constant should be increasing as a function of confining pressure. This paper aims to present a theoretical relationship between Poisson’s ratio of intact rock and the confining pressure, using the Hoek-Brown failure criteria. It was assumed that the Poisson’s ratio is increasing linearly, and at the brittle-ductile transaction point, it is 0.5. The proposed relationship can be extended to rock mass, using the Geological Strength Index (GSI)

New insight into cataract formation -- enhanced stability through mutual attraction

Small-angle neutron scattering experiments and molecular dynamics simulations combined with an application of concepts from soft matter physics to complex protein mixtures provide new insight into the stability of eye lens protein mixtures. Exploring this colloid-protein analogy we demonstrate that weak attractions between unlike proteins help to maintain lens transparency in an extremely sensitive and non-monotonic manner. These results not only represent an important step towards a better understanding of protein condensation diseases such as cataract formation, but provide general guidelines for tuning the stability of colloid mixtures, a topic relevant for soft matter physics and industrial applications.Comment: 4 pages, 4 figures. Accepted for publication on Phys. Rev. Let