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This work provides an environmental approach to utilise Blast furnace slag (BFS) waste for the processing of aluminium oxide (Al2O3-BFS) as an efficient adsorbent for uranium removal from wastewater. The composition of BFS is less variable and this makes it a low cost and abundant raw material for preparing a solid base Al2O3-BFS. The silica material was initially removed and then the aluminium content was separated by precipitation with sodium hydroxide depending on pH control (pH 5.5). The raw BFS and Al2O3-BFS were characterised via various methods, such as; XRD, Zeta potential, N2 adsorption-desorption isotherm, DLS, and FT-IR. BFS exhibited the typical type III isotherm with an H3-type hysteresis loop. The curve of Al2O3-BFS exhibited the typical IV isotherms with a H2-type hysteresis loop. The BET surface and average pore sizes of the Al2O3-BFS are 137.7 m2 g-1 and 3.9 nm, respectively. Experiments and discussions were performed in terms of balance, isothermal, kinetic, and applicability. The finding provides proof of the ability of synthesised Al2O3-BFS to remove U(VI) ions from wastewater as an efficient adsorbent with a maximum sorption capacity value of 62 mg/g. The pseudo second, Langmuir and Dubinin-Radushkevich models were found suitable to explain the rate kinetics and isotherm of uranium removal. Uranium sorption on Al2O3-BFS may occur via inner-sphere complex and ion-exchange between uranium ions and HO-Al2O3-BFS groups. The higher elution efficiency of Al2O3-BFS indicates a promising adsorbent in the technology of U(VI) removal. [ABSTRACT FROM AUTHOR]

Summary: A new bipyridine‐containing manganese (II) complex, namely [(BPy)2MnCl2]·0.5H2O (MnC), was synthesized and characterized. Spectral and X‐ray structural features revealed that MnC has an octahedral environment around Mn(II). Graphene oxide (GO) was noncovalently functionalized with the MnC. MnC‐ and (MnC/GO)‐modified glassy carbon (GC) interfaces with different loading densities (0.2, 0.4, 0.8, and 1.0 mg cm−2) were tested as electrocatalysts for efficient generation of H2 in 0.1 M KOH solution. The GC‐MnC catalysts exhibited high electrocatalytic activity for the HER, which enhances upon increasing the catalyst's loading density. The GC‐MnC catalyst's HER activity, at any tested loading density, was found to further increase upon supporting MnC on GO. The best performing electrocatalyst, namely GC‐(MnC/GO) with a loading density of 1.0 mg cm−2, exhibited high HER catalytic activity with a low onset potential value of −22 mV vs. reference hydrogen electrode (RHE) and a high exchange current density of 0.75 mA cm−2. It delivered a current density of 10 mA cm−2 at an overpotential value of 119 mV. In addition, it recorded a Tafel slope value of −114 mV dec−1. These HER electrochemical kinetic parameters approached those measured here for the commercial Pt/C under the same operating conditions (−10 mV vs. RHE, 0.88 mA cm−2, 113 mV dec−1, and 110 mV to yield a current density of 10 mA cm−2) and also comparable to the most active molecular electrocatalysts for H2 generation from aqueous alkaline electrolytes published in the literature. The long‐term stability of the best performing electrocatalyst, namely GC‐MnC (1.0 mg cm−2)/GO, was evaluated using cyclic voltammetry (repetitive cycling up to 5000 cycles) and chronoamperometry (48 hours) techniques, and the obtained results revealed its promising stability. A plausible mechanism for the interaction of MnC with GO was proposed based on density functional theory (DFT) calculations. DFT calculations confirmed the catalytic role of the supporting material (GO) on the fabricated metal complex in catalyzing the HER. [ABSTRACT FROM AUTHOR]

The molecular complexes between thiobarbituric acid (TBA) and halogen molecules (X2 = I2, Br2, and Cl2) in different solvents are explored. Density functional theory (DFT) calculations at rwb97xd/lanl2dz were used to corroborate the experimental electronic and optical properties of the molecular adducts. Experimental results (Fourier transform infrared spectroscopy) show the stability of the complexes by halogen bonding (XB) and competitive hydrogen bonding (HB), which was supported by the DFT calculations. The molecular electrostatic potential and the frontier orbital calculations supported engagement of the thione group in XB rather than the carbonyl group. Based on the Hirshfeld atomic population, noncovalent interaction, and natural bond orbital analysis, the stability of TBAX2 adducts increases in the order TBACl2 > TBABr2 > TBAI2, where the larger charge transfer and highest stabilization energy were calculated for TBACl2 adducts. [ABSTRACT FROM AUTHOR]

The present investigation aimed to evaluate the effect of dietary chitosan supplementation on growth performance, body composition, immune response and histopathology of Nile tilapia, and also the in vitro antibacterial activity of chitosan against Streptococcus agalactiae (S. agalactiae). About 180 fish (average body weight 39.3 ± 0.3 g) were randomly divided into three groups according to chitosan supplementation: control group (basal diet without chitosan), Ch3 group (3 g chitosan/kg diet) and Ch5 group (5 g chitosan/kg diet). Growth performance parameters and body proximate composition were measured before infection but biochemical parameters and lysozyme and antibacterial activities before and after experimental infection. Results of the present investigation showed dietary chitosan (5 g chitosan/kg diet) significantly (p <.05) improved growth performance parameters, body composition (dry matter, crude protein, ether extract, ash, and carbohydrate) and serum biochemistry (total protein, albumin, globulin, with no effect on AST, ALT, urea and creatinine) before infection in Ch5 group than the control. After infection, liver enzymes (serum AST and ALT) were maintained lower in fish fed Ch3 or Ch5 than the control. Serum lysozyme and bactericidal activities significantly increased (p <.05) in chitosan groups before and after the challenge. The mortality rate was markedly reduced in the Ch3 group and prohibited in the Ch5 group after the experimental infection. In conclusion, feeding 3 or 5 g chitosan/kg diet increased the growth rate and improved FCR of Nile tilapia. In addition, it reduced mortality by its antibacterial and immunostimulant effects. [ABSTRACT FROM AUTHOR]