Narrow Results

Our purpose in this paper is to modify the original proximity potential by universal function available in the literature. A potential model with Yukawa proximity potential has been considered according to the modified model fusion reactions of ${}^{92}\mathrm{\text{Zr}}+{}^{12}\mathrm{\text{C}}$, ${}^{16}\mathrm{\text{O}}+{}^{92}\mathrm{\text{Zr}}$, ${}^{28}\mathrm{\text{Si}}+{}^{92}\mathrm{\text{Zr}}$, ${}^{16}\mathrm{\text{O}}+{}^{144}\mathrm{\text{m}}$, ${}^{28}\mathrm{\text{Si}}+{}^{28}\mathrm{\text{Si}}$, ${}^{28}\mathrm{\text{Si}}+{}^{29}\mathrm{\text{Si}}$, ${}^{28}\mathrm{\text{Si}}+{}^{30}\mathrm{\text{Si}}$, ${}^{24}\mathrm{\text{Mg}}+{}^{24}\mathrm{\text{Mg}}$, ${}^{24}\mathrm{\text{Mg}}+{}^{26}\mathrm{\text{Mg}}$ and ${}^{24}\mathrm{\text{Mg}}+{}^{28}\mathrm{\text{Si}}$, ${}^{26}\mathrm{\text{Mg}}+{}^{28}\mathrm{\text{Si}}$, ${}^{24}\mathrm{\text{Mg}}+{}^{30}\mathrm{\text{Si}}$, ${}^{26}\mathrm{\text{Mg}}+{}^{30}\mathrm{\text{Si}}$ which have been discussed in detail. The results have a good agreement with the experimental data.

In this work we have discussed dependence of surface tension coefficient that appears in proximity potential and energy of incident nucleus. The obtained results from study of the fusion barrier heights and positions for 44 reactions with z≥8 reveal that this modification on the formalism of proximity model leads to a better agreement between computed fusion barrier heights and positions and experimental data.

In this paper, the proximity formalism which has been recently generalized to calculate the nuclear potential in the fusion reaction of deformed nuclei, employed to study the ³⁵Cl+⁹²Zr system. We also employ different versions of surface energy coefficients and discuss the effect of surface energy coefficients in the proximity potential. Comparison between results of double-folding (DF) and proximity model (PM) are made.

The Coulomb barrier heights are calculated by using the proximity potential with a new universal function in comparison with the results of proximity potentials Prox77, AW95, Bass73, BW91, CW76, DP and Ng80. It is found that the new results of Coulomb barrier heights are better than those of most proximity potentials. Then this proximity potential with the new universal function was used to calculate the Coulomb barrier positions and heights from light fusion systems to heavy fusion systems. The parametrized formulas are obtained for Coulomb barrier height and position, and can reproduce most of calculated barrier heights and positions within the accuracy of $\pm 1\%$.

Conductivity-frequency and capacitance-frequency characteristics of mixed oxides Al–In₂O₃–SnO₂–Al structure are examined to elicit any correlation with the conduction mechanisms most often observed in thin film work. The existence of Schottky barriers is believed to be due to a strong donor band in the insulator established during the vacuum evaporation when a layer of mixed oxides In₂O₃–SnO₂ system is sandwiched between two metal electrodes. Low values of activation energy at low temperatures indicate that the transport of the carriers between localized states is mainly due to electronic hopping over the barrier separating the two nearest neighbor sites. The increase in the formation of ionized donors with increase in temperature during electrical measurements indicates that electronic part of the conductivity is higher than the ionic part. The initial increase in conductivity with increase in Sn content in In₂O₃ lattice is caused by the Sn atom substitution of In atom, giving out one extra electron. The decrease in electrical conductivity above the critical Sn content (10 mol% SnO₂) is caused by the defects formed by Sn atoms, which act as carrier traps rather than electron donors. The increase in electrical conductivity with film thickness is caused by the increase in free carriers density, which is generated by oxygen vacancy acting as two electron donor. The increase in conductivity with substrate and annealing temperatures is due to either the severe deficiency of oxygen, which deteriorates the film properties and reduces the mobility of the carriers or to the diffusion of Sn atoms from interstitial locations into the In cation sites and formation of indium species of lower oxidation state (In²⁺). Calculations of C and σ_ac from tan δ measurements suggest that there is some kind of space-charge polarization in the material, caused by the storage of carriers at the electrodes. Capacitance decreases not only with the rise of frequency but also with the lowering of temperature. At low temperatures the major contribution to capacitance arises from the ionic polarization, however, with the increase of temperature the contribution from orientation polarization would considerably increase. The decrease in capacitance with the increase in frequency may be attributed to interfacial polarization.

We performed the nonadiabatic time-dependent wave packet calculation on the four diabatic potential energy surfaces, which have the different barrier height, to investigate the contribution of the noncollinear channel for the F (²P) + H₂/D₂ (v = j = 0) reactions. The reaction probabilities, integral cross-sections, and rate constants are presented. The results indicate that the probabilities as the function of the collision energy have an obvious translation. The reactive activity of the reactions comes from the noncollinear reactive channel. The bent barrier height would decrease the reactive activity. The integral cross-sections are in the order of AWS < LWA-5 < LWA-78 ≈ MASW, which is opposite to that of the bent barrier height. At the lower temperature, the difference of the rate constants is unambiguous. As the temperature increases, the difference reduces. At the higher temperature, the rate constants computed on the four potential energy surfaces are close.