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‘Goldberg criterion’ [Goldberg and Smith, Phys. Rev. Lett. 29 (1972) 500] tells that at sufficiently high energies, where pronounced refractive scattering with nuclear rainbow oscillations are followed by an ‘exponential-type falloff’ in the angular distribution, discrete ambiguities are eliminated for the deep monotonic potential. The criterion is also confirmed in the work of Bartnitzky et al. [Phys. Lett. B 365 (1996) 23] on the 16O+16O elastic scattering in the energy range of 250 - 704 MeV. However, their finding ‘using model-independent potentials’ suggests that heavy-ion elastic scattering data unambiguously favour deep potentials. The Goldberg criterion is examined in our work for non-monotonic shallow potentials using the 16O+16O elastic scattering at energy region up to 350 MeV.

A novel method for the determination of the yet not well-known quantity of nuclear incompressibility, K is presented. Non-monotonic (NM) nucleus-nucleus potentials from the energy-density functional (EDF) theory including the Pauli principle have been considered for K in the range 188-266 MeV. The experimental cross sections of 16O+16O elastic scattering over the 31-350 MeV incident energies have been analyzed in the optical model using the NM potentials. Sensitivity of K on the elastic scattering data is studied and its value for infinite cold nuclear matter deduced to be 222 ± 5 MeV

This work illustrates, for the first time, the analysis of tensor analyzing powers (T 20, T 21, T 22) along with the differential cross-section (CS) and the vector analyzing power iT 11 for the 6Li+12C elastic scattering at 30 and 50 MeVwithin the framework of an optical model (OM) using microscopic shallow non-monotonic (NM) potentials. The NM potential is generated from the energy density functional formalism (EDF) [Brueckner et al., Phys. Rev., 168 (1968) 1184] using a realistic two-nucleon interaction incorporating Pauli Exclusion principle. The shallow NM potential can describe the experimental angular distributions of CS and analyzing powers of the elastic scattering data. The OM analysis of the data at this energy does not indicate their sensitivity on the nuclear matter incompressibility K.

The effect of sintering temperatures (Ts ) on the structural and magnetic properties of Ni0.6Zn0.4Fe2O4(NZFO) ferrites synthesized by conventional double sintering method has been reported. The samples are sintered at 1200, 1250 and 1300 °C. The X-ray diffraction (XRD) analysis reveals the formation of a single phase cubic spinel structure of the sample. The magnetic parameters such as saturation magnetization, Ms ; coercive field, Hc ; remanent magnetization, Mr and Bohr magneton, µ B are determined and compared with reported values. The obtained values are found to be 71.94 emu/gm and 1.2 Oe for Ms and Hc , respectively at Ts = 1300°C sample. Curie temperature (Tc ) for various Ts has also been calculated. It is noteworthy that the sample with a very low Hc could be used in transformer core and inductor applications.

The anomalous behaviour of dc charge dynamics in high-Tc cuprates cannot be explained by the prevalent Boltzman transport theory. In high-Tc cuprates the in-plane and out-of-plane dc resistivities exhibit high anisotropy and unconventional temperature dependence. In this study we have modeled the temperature (T) and hole content (p) dependent in-plane resistivity, ρa (T, p), of pure and Ca doped Y123 (Y(Ca)Ba2Cu3O7- δ ). We have adapted and extended the formalism developed by Naqib et al. (Physica C 471 1598 (2011)) by taking account of two generic features present in all hole doped cuprates, namely - (i) the presence of the pseudogap in the quasiparticle spectrum and (ii) high-T linear behavior, to elucidate non-Fermi liquid ρa (T, p) of Y(Ca)Ba2Cu3O7- δ over a wide range of temperature and hole contents. The characteristic pseudogap energy scale, εg (p), extracted from the analysis of the resistivity data was found to agree well with those found in a variety of earlier studies. Other extracted parameters from the analysis of ρp (T, p) data showed methodical variations with the variation of hole content. Important features of the analysis are briefly discussed.

The study intends to measure secondary level students’ critical thinking skills. This study follows a survey method and is a part of a doctoral dissertation focusing on promoting critical thinking skills of environmental education for achieving sustainable development goals (SDGs). The data were collected by using the Critical Thinking Skills test on Environmental Education (CTSEE) comprises of 27 items. The participants were the 8th grade students (N=444) from 13 secondary schools that cover four administrative districts of Bangladesh. The Instrument was adopted from previous research that consists of three aspects (Conclusion, Inference, and Identifying Bias) of critical thinking skills. The result shows that the students’ critical thinking skills on environmental issues can be categorized into the poor and very poor category, and there are statistically significant differences between male and female students. The study will be used as the reference for developing students’ critical thinking skills about the surrounding environment-related problem in line with achieving the globally decided environmental sustainability as well as sustainable development goals.

Synopsis A complex optical potential (OP) is employed within the framework of the Dirac partial wave method to study the critical minima (CM) in the differential cross sections and the spin polarization for the elastic scattering of electrons by the Sr atom in the energy range Ei = 1-1000 eV. The complex optical potential is composed of the static, exchange, polarization and absorption potentials. The number of CM points has been found to be 7 in the DCSs of e-Sr scattering, while the number of maximum spin polarization points observed is 13.

Synopsis Vaisburd and Evdokimov proposed an empirical VE model to calculate the electron impact single ionization cross-sections of atoms and molecules. The extension of the modified VE model (MVE) has been proposed incorporating the relativistic effects. This model is applied to investigate the total L-shell as well as L1-, L2- and L3-subshells ionization cross-sections of various atomic targets with atomic numbers Z =1892 for incident energies up to 1 GeV. The results from the MVE model are compared with the available experimental data and theoretical findings.

Synopsis Theoretical differential, elastic, total, momentum transfer, viscosity cross sections and spin-polarization for the elastic scattering of e∓ by H2 O molecule in the energy range 10 eV-10 keV have been calculated. These calculations have been carried out within the framework the Dirac partial wave analysis. We have employed a complex optical potential and additivity rule (AR) to compute the cross sections. Present results reasonably agree with available experimental data and other theoretical findings.

Among several existing distance measures, perhaps Euclidean distance is the most used tool to calculate distances and then Manhattan distance measure, though which distance measure is suitable depends on the problems. In the field of Design of Experiments (DoEs) especially in simulation domain Latin Hypercube design (LHD) is a well-known approach to find out design points for experiments/simulations. Generally, randomly generated LHDs show poor space-filling property. But space-filling is one of the most required impotent properties for DoE. So researchers search optimal LHD in the sense of space-filling. Some authors considered Euclidean distance measure on the other hand some other authors considered Manhattan distance measure to find out optimal LHD regarding space-filling. It is obvious that both optimal LHDs are not identical. So it is a crucial asked - which measure provided better space-filling? The main problem is that there is no any relation among the distance measures especially Euclidean distance measure and Manhattan distance measure. In this article we have established some relations and bounds between Euclidean distance measures and Manhattan distance measures in perspective of LHD. Finally some experimental results are compared namely maximin LHDs measured by both Euclidean distance measure and Manhattan distance measures by using some proposed transformation techniques.

In this work, the heterostructure carbon supported tin/tin oxide (Sn/SnO2) photocatalysts has been developed. The target heterostructure was prepared by precipitation method followed by carbothermal reduction using tin tetrachloride (SnCl4) as precursor for SnO2, activated carbon as reducing agent, and ammonia solution as precipitating agent. The photocatalytic activity of the as-prepared photocatalysts was investigated by degrading methylene blue (MB) dye. The photocatalytic decomposition of methylene blue in solution under UV light irradiation revealed that the heterostructure Sn/SnO2 photocatalysts catalyst led to higher activities than pure SnO2. The suppression of charge separation in the heterostructure carbon supported Sn/SnO2 due to space charge region between SnO2 and Sn led to higher catalytic activity for the degradation of MB. The results also showed that the pH of solution had a direct influence on the photocatalysis process and neutral pH was favorable for the degradation of MB. In addition, the photocatalysts could be easily recycled without significant change in the catalytic activity which indicated the stability and reproducibility of the catalysts. The results suggested that the as-prepared carbon supported Sn/SnO2 can be applied as a promising photocatalyst for the treatment of wastewater containing organic pollutants.

Electron impact ionization cross sections for E ≤ 10 keV are presented for O and its isoelectronic series (F+, Ne2+ and Si6+ ions) and compared with experimental and other theoretical results.

We propose an extension of our recently modified simplified-improved-binary-encounter dipole (MUIBED) model [1] suitable even for relativistic energies. This new model (XMUBED) is applied to calculate the electron impact single M-subshell ionization cross-sections for atomic targets with various charges Z (79 ≤ Z ≤ 92). The parameters of the MUIBED model for the M-shell ionization calculations are modified to account well for fourteen atomic targets (between Au and U) for the inner M-subshell ionization cross sections.