[en] In a previous paper, one of us (UL) constructed an exact analytical expression for the irregular (Jost) solution, off the energy shell, for the Hulth´en potential by using the method of ordinary differential equation along with the properties of certain special functions of mathematical physics. In the present text, closed form expressions for the off-shell irregular solution and half-off-shell Tmatrix for motion in the Hulth´en potential are re-derived by using the direct integration approach to the problem under consideration. We demonstrate the usefulness of our expressions through some model calculations and achieve excellent agreement between bound-and scattering-state observables and standard results.

[en] The phase function method/variable phase approach to potential scattering is exploited to calculate the phase shifts for nucleon-nucleon systems in low and intermediate energy regions by representing the nuclear part of the interaction by the Hellmann potential while the electromagnetic part by the Coulomb one. In addition, the differential and total scattering cross-sections are estimated with our phase parameters. Results reproduced by the concerned potential are in good agreement with the previous works in the literature. (author)

[en] The composites of BiFeO_3-PbTiO_3 (BF-PT) and BiFeO_3-PbZrO_3 (BF-PZ) were prepared by mixed oxide method. Room temperature X-ray diffraction data confirms the rhombohedral and tetragonal crystal structure respectively. Dielectric constant of BF-PZ is found to give high value compared to BF-PT and hence, there is an increase value of ac conductivity for the former. Both the composites show negative temperature coefficient of resistance (NTCR) behavior. The activation energies of BF-PT and BF-PZ are found to be 0.35 eV and 0.53 eV respectively. The d_3_3 coefficients are found to be 2.0 and 2.1 pC/N for BF-PT and BF-PZ respectively

[en] The study dealt with seawater intrusion process in a coastal aquifer system in the Mahanadi river delta region in the east coast of India along the Bay of Bengal. The aquifers of Mahanadi delta are characterized as shallow aquifers (< 50 m) and deeper aquifers (> 50 m). Electrical conductivity (EC) of groundwater varied from a fresh of 146 μS/cm (NW of the Mahanadi delta) to a saline of 33,900 μS/cm (close to sea coast) with cation dominance in the order Na⁺ > Ca²⁺ > Mg²⁺ > K⁺ and anion dominance of Cl⁻ > ${\text{HCO}}_3^{-<!--\; ???\; -->}$ > ${\text{SO}}_4^{2-<!--\; ???\; -->}$. The hydrochemical facies changed from Ca–Mg–Na–HCO₃ type to Na–Cl type along the groundwater flow direction due to ion exchange processes. A strong positive correlation (r > 0.9) between Cl⁻ with EC, Na⁺, Mg²⁺, Ca²⁺, ${\text{SO}}_4^{2-<!--\; ???\; -->}$ and K⁺ was observed, which indicated the influence of seawater on coastal aquifer. The ionic ratios (Na⁺/Cl⁻, ${\text{HCO}}_3^{-<!--\; ???\; -->}$/Cl⁻, Mg²⁺/Ca²⁺, ${\text{SO}}_4^{2-<!--\; ???\; -->}$/Cl⁻, Ca²⁺/(${\text{HCO}}_3^{-<!--\; ???\; -->}$/${\text{SO}}_4^{2-<!--\; ???\; -->}$)) also suggested that the groundwater is affected by seawater intrusion. Stable isotope compositions (δ¹⁸O and δ²H) varied from − 1.86 to − 6.87 ‰ for δ¹⁸O and from − 10.79 to − 45.42 ‰ for δ²H, implying the mixing of saline water and fresh groundwater in the coastal region of the Mahanadi delta. The proportion of seawater in groundwater was estimated to vary from 0% in the upper-delta formation to 72% in the lower-delta formation of the Mahanadi delta (close to seacoast), which was due to inland intrusion of seawater. In a first ever study on this coastal aquifer along the Bay of Bengal, where a large population is dependent on agriculture, seawater intrusion into the fresh groundwater has been quantified. The issue of seawater intrusion into the coastal aquifer in this region may become a serious disaster, if appropriate management strategies are not implemented in time.

[en] A regular solution for the Manning–Rosen potential is constructed by adapting the differential equation approach to the problem. The Jost solution and the Jost function are found by exploiting the relation between regular and irregular solutions. The Jost function thus obtained is applied for the first time to find bound state energies and the scattering phase shifts for nuclear systems. (paper)

[en] 0.5BiGd_xFe_1−xO₃−0.5PbTiO₃ with x=0.05, 0.10, 0.15, 0.20 composite was prepared by mixed oxide method. Structural characterization was performed by X-ray diffraction and studied that the materials show tetragonal structure at room temperature for all concentration of Gd. Studies of dielectric properties (ε_r and tanδ) of the above compound at different frequencies in a wide range of temperature (25°-500°C) with an impedance analyser revealed that the dielectric constant increases with increase in Gd concentration as well temperature and the compound do not have any dielectric anomaly in the studied frequency and temperature range

[en] Although often used in molecular dynamics, in this work the Manning–Rosen potential is parameterized to compute the scattering phase shifts for the nucleon–nucleon and the alpha-nucleon systems by exploiting the standard phase function method. We obtain excellent agreement in phase shifts with the more sophisticated calculations up to partial waves $\mathrm{\ell <!--\; ???\; -->}=2.$ (paper)

[en] The s-wave on-shell Jost solution for the Manning-Rosen potential is constructed via the ordinary differential equation approach to the problem. The corresponding off-shell Jost function is calculated by using the integral representation of the off-shell Jost function in a single channel scattering. The half off-shell T- matrix is obtained from the knowledge of the off-shell Jost function. Our constructed expressions for the Jost functions are applied to compute T-matrix, quasi-elastic phase shifts and the scattering phase shifts for the nuclear systems. (paper)