Narrow Results

The alpha-decay half lives of superheavy elements have been calculated in the framework of WKB method. The effective potential has been considered as summation of the deformed Woods–Saxon nuclear potential, deformed Coulomb potential and centrifugal term. The quadrupole, hexadecapole and hexacontatetrapole deformations have been included in the calculation. The effect of hexacontatetrapole deformation on the potential barrier has been presented, separately. The good agreement between theory and experiment has been observed for alpha-decay half-lives of heavy and superheavy elements.

For a test particle approaching a rapidly rotating black hole we find a range of values of the particle’s energy and angular momentum, on the order of 1% or more of the corresponding values of the hole, such that three conditions are satisfied. (1) The particle can reach the horizon. (2) After absorption the new hole still has a horizon. (3) The area of the new hole is less than the area of the original one, in apparent violation of a theorem of Hawking. We offer support for the claim that the test particle approximation is the cause of the violation.

The geometric structure, energy barrier and electronic properties of H-incorporated ${\mathrm{\text{Ti}}}_3{\mathrm{\text{SiC}}}_2/\mathrm{\text{Zr}}$ heterojunctions were investigated by first-principles calculations. Hydrogen atom settles in ${\mathrm{\text{Ti}}}_3{\mathrm{\text{SiC}}}_2/\mathrm{\text{Zr}}$ as interstitial impurity due to its small radius. Through calculating and analyzing the total energies of H-incorporated ${\mathrm{\text{Ti}}}_3{\mathrm{\text{SiC}}}_2/\mathrm{\text{Zr}}$ heterojunction, a much higher potential barrier (1.75 eV) was found when H atom diffuses from the interface into the ${\mathrm{\text{Ti}}}_3{\mathrm{\text{SiC}}}_2$ material than that (0.25 eV) into the Zr metal. The encountered potential barriers of H atom diffusing from vacuum into the ${\mathrm{\text{Ti}}}_3{\mathrm{\text{SiC}}}_2$ and Zr metal are also calculated, and they are both positive. These findings indicate that ${\mathrm{\text{Ti}}}_3{\mathrm{\text{SiC}}}_2$ is a suitable coating material to prevent the hydrogen embrittlement and corrosion in Zr metal. The electronic properties and valence bond properties of H-incorporated ${\mathrm{\text{Ti}}}_3{\mathrm{\text{SiC}}}_2/\mathrm{\text{Zr}}$ were analyzed based on the band structure, electronic density of states and Mulliken distribution. The calculated results show that all the H-incorporated ${\mathrm{\text{Ti}}}_3{\mathrm{\text{SiC}}}_2/\mathrm{\text{Zr}}$ heterojunctions exhibit metallic, covalent and ionic properties. These investigations may provide new insight into the underlying mechanisms of hydrogen diffusion in the ${\mathrm{\text{Ti}}}_3{\mathrm{\text{SiC}}}_2/\mathrm{\text{Zr}}$ heterojunction.

Grain boundaries and their electric potential were studied in connection with the electric conduction in polycrystalline copper using a scanning tunneling microscope (STM). It was found that the grain boundaries consist mainly of cuprous oxide (Cu₂O) and electric potential barriers are formed at most grain boundaries.

We study the half-lives of some Pt isotopes via the alpha-decay process and a modified barrier penetration formula different from the traditional barrier potentials. Comparison with the existing data is quite motivating.

The product angular momentum polarization of the Cl + C₂D₆ → DCl + C₂D₅ reaction is calculated via the quasiclassical trajectory (QCT) method at the collision energy of 0.25 eV. A new London–Eyring–Polanyi–Sato (LEPS) potential energy surface (PES) is used in this reaction. There is a "late" barrier and a "deep" well on this new LEPS PES. The four polarization-dependent "generalized" differential cross sections (PDDCSs) are presented in the center-of-mass frame. In the meantime, the distributions of P(ϕ_r), P(θ_r), and P(θ_r, ϕ_r) are calculated. The calculations are in good agreement with the experimental data. In addition, the rotational alignment factors , , and in the stationary-target frame (STF) are also calculated.

Thin nanocomposite films based on tin dioxide with a low content of zinc oxide (0.5–5mol.%) were obtained by the sol–gel method. The synthesized films are 300–600nm thick and contains pore sizes of 19–29nm. The resulting ZnO–SnO₂ films were comprehensively studied by atomic force and Kelvin probe force microscopy, X-ray diffraction, scanning electron microscopy, and high-resolution X-ray photoelectron spectroscopy spectra. The photoconductivity parameters on exposure to light with a wavelength of 470nm were also studied. The study of the photosensitivity kinetics of ZnO–SnO₂ films showed that the film with the Zn:Sn ratio equal to 0.5:99.5 has the minimum value of the charge carrier generation time constant. Measurements of the activation energy of the conductivity, potential barrier, and surface potential of ZnO–SnO₂ films showed that these parameters have maxima at ZnO concentrations of 0.5mol.% and 1mol.%. Films with 1mol.% ZnO exhibit high response values when exposed to 5–50ppm of nitrogen dioxide at operating temperatures of $200^{\circ }$C and $250^{\circ }$C.