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Nihonium, Nh, is one of the newly synthesized elements. It has a high atomic number of 113, putting it in the same group as thallium, Tl. The properties of this element are largely unknown, and it is of interest to assess its (hypothetical) properties in the solid state. Elements in the same group of the periodic table as Nh are known to form binary and even tertiary compounds that have important semiconductor properties. This also makes studies on Nh attractive. We performed an ab initio computational study of its electronic structure adopting the local density and generalized gradient approximations for the exchange-correlation potential. The energy band diagrams, the total energies per volume of unit cells and density of states of Nh were compared to the known experimental and theoretical properties of elemental Tl, which lies in the same column above Nh in the periodic table. Within the limits of density-functional theory, it was found that solid Nh is expected to be a metal that is most stable in a hexagonal close packing structure.

There is a substantial amount of literature dealing with many aspects of synthesis and characterization of pure and doped binary compounds including Mn-doped ZnO which has been widely studied due to its superb properties as a dilute magnetic semiconductor (DMS).Aspects concerning doping limits for these compounds is an important stage in the search for new materials. Samples of Zn1-xMnxO nanocrystal were synthesized at temperatures of 180 °C and 200 °C using wet or liquid phase synthesis method. Dopant concentrations x=0.5, 1, 1.5, 2, 2.5, 5, 10, 20, 30, 40 and 50 per cent were studied. Powder x-ray diffraction (PXRD) patterns of the samples were analyzed with a view to determining the onset of secondary phases and hence the solubility limit of the dopant. The solubility limit for Mn in ZnO samples synthesized at temperature of 200 °C is realized at x

A simple low cost chemical route has been used to synthesize cupric oxide nanoparticles. The synthesized CuO nanoparticles were characterized using XRD, TEM and UV-absorption. X-ray diffraction analysis showed the synthesized nanoparticles to be a pure cupric oxide. EDAX analysis showed the presence of copper and Oxygen in the as prepared CuO nano particles, with the AAS indicating that Cu2+ represented 53.5% of the sample. The particle size and particle size distribution of the cupric oxide nanoparticles were obtained by transmission electron microscopy (TEM) whereas the crystallite size and crystallite size distribution were obtained by X-ray diffraction. The particle size was found to be between 20 nm and 60 nm. The particle size distribution obtained from cumulative percentage frequency plots features a log-normal function. Absorbance measurements and analysis showed that the material has an absorbance peak at 314 nm and energy bandgap of 1.48 eV, making it a good candidate for photovoltaic applications.

Dyes used by the textile, tannery, and food industries tend to pollute water bodies and must be removed to get clean water. Hydroxyapatite (HAP) was synthesized from eggshells using the wet precipitation process. The as-synthesized HAP was characterized using Fourier Transform Infrared (FTIR) and X-ray powder diffraction (XRD). The synthesized HAP was mixed with three different clays: halloysite (HNT), kaolinite (KAO), and bentonite (BENT). The removal efficiency values of methylene blue (MB) from the data showed that HAP-BENT adsorbents had higher values, followed by HAP-HNT and then HAP-KAO adsorbents. The combined masses of 24 mg, 34.5 mg, and 33 mg (representing 20%, 15%, and 10% of HAP-BENT mass) had average adsorption capacity values of 20.7 mg/g, 17.2 mg/g, and 17.9 mg/g, respectively. For each mass percentage, the adsorption capacity values were found to decrease with adsorbent dosage. The HAP-BENT composites had removal efficiency values of 98.4, 91.9%, and 91.9%, respectively. Adsorption data for the HAP-BENT adsorbents were found to be well described by the Langmuir isotherm model and pseudo-second-order kinetic model. The effect of temperature on adsorption capacity was evaluated and thermodynamical modeling was undertaken. The thermodynamical modeling predicts that based on the value of the change in enthalpy and Gibbs free energy the process was exothermic and spontaneous. This work confirms the potential of HAP-clay composites in removing MB from water.

Pure and transition metal (TM)-doped ZnO nanocrystals were synthesized using a wet-chemical process. Synthesis was carried out in distilled water at 85 °C followed by calcining the as-prepared powders at 280 °C and 600 °C. Co, Mn and Fe doping at 4 and 8 mol % was achieved by adding CoCl2.6H2O, MnCl2 .4H2O and FeCl2 .4H2O respectively during the synthesis. Crystal phase characterization was carried out by X-ray powder diffraction (XRD) which confirmed the formation of ZnO in the wurtzite polymorph. The band gap energy of the nanocrystals was measured by both photoluminescence spectroscopy (using the Near Band Edge Emission) and UV-Vis absorption spectroscopy, using a modified version of the Tauc law. Widening of the band gap energy from 3.23 eV to 3.33 eV with increased doping concentration was observed for all the dopants. Ab-initio simulations of doped and undoped ZnO crystals using density functional theory as implemented in the Quantum Espresso package confirmed the increase in the band gap energies with doping concentration.

Powders consisting of nanoparticles of zinc peroxide were prepared via a simple hydrothermal process using zinc acetate dihydrate and hydrogen peroxide precursors. The size of the crystallites was determined using x-ray powder diffraction. Over a period of 5 hours the crystallite radius increased from 4 nm – 9 nm at a temperature of 68 °C ± 5 °C, with growth rate constant of 0.23 nm3 min−1 calculated using the Lifshitz, Slyozov, and Wagner model. The powders were further characterised with High Resolution Transmission Electron Microscopy, Energy Dispersive X-ray analysis, and Small Angle X-ray Scattering, showing well-crystallised ZnO2 nanoparticles.

Rice ( Oryza sativa L.) is a staple crop in Ghana and much of West Africa, where it serves as an important convenience food for urban consumers. The objective of this study was to determine the effect of gamma irradiation as insect disinfestation technique on some physicochemical, functional and pasting properties of selected locally-produced rice cultivars in Ghana. Four local rice cultivars and an imported (commercial) type were purchased, cleaned and irradiated at doses of 0.0, 0.25, 0.50, 0.75, 1.0 and 1.5 kGy. The irradiated rice cultivars were milled and their physicochemical, functional and pasting properties determined. There were reductions in pH and swelling power, as well as increase in solubility of rice cultivars after gamma irradiation. Gamma irradiation did not change the XRD pattern of the rice cultivars. Gamma irradiation significantly (P