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Uranium is a key element to improve nuclear energy demands, and thereby the extraction of uranium from seawater is a strategic way to address uranium sustainability. Herein, a novel two‐dimensional porous aromatic framework (AO‐PAF), which possesses an ultra‐microporous architecture with an ordered structure, excellent stability and selectivity of uranium extraction from a liquid phase. AO‐PAF shows excellent uranium adsorption capacities of 637 (mg/g) and 3.22 (mg/g) in simulated and natural seawater attributable to the selective uranium coordinating groups on highly accessible pores on the walls of open channels. In addition, benefiting from the super‐hydrophilicity due to the presence of amidoxime groups attributes high selectivity and ultrafast kinetics with an uptake rate of 0.43 ± 0.03 (mg/g·day) and allowing half‐saturation within 1.35 ± 0.09 days. This strategy demonstrates the potential of PAF not only recovery of uranium and can be extended for other applications by sensible planning of target ligands. [ABSTRACT FROM AUTHOR]

An economical and highly uranium extraction from seawater remains a crucial task for energy sources and environmental safety. Aiming for improving the mass transfer rate of uranium from seawater, a new synthetic strategy was adopted to synthesize two‐dimensional‐open channel microporous bioadsorbent for uranium extraction from seawater. Herein, a vapor phase modification approach was adopted to graft divinylbenzene (DVB), and polyacrylonitrile (AN) onto the surfaces of microporous frameworks via a free radical polymerization method. The postsynthetic functionalization was carried out by hydrothermal process, where amidoxime groups are structure‐directing agents to trap uranium. Furthermore, amidoxime groups not only enhanced hydrophilicity but also adjusts adsorbents pKa. AO‐Fc faces minimum interference of competing ions and achieves a high uranium adsorption capacity of 8.57 ± 0.02 and 409 ± 1 mg/g in seawater and simulated solution. Despite its stable structure, AO‐Fc exhibits a long life span and negligible weight loss revealed AO‐Fc could be applied as a potential adsorbent for radionuclides. [ABSTRACT FROM AUTHOR]

The present paper studies a fractional‐order SEIR epidemic model for the transmission dynamics of infectious diseases such as HIV and HBV that spreads in the host population. The total host population is considered bounded, and Holling type‐II saturation incidence rate is involved as the infection term. Using the proposed SEIR epidemic model, the threshold quantity, namely, basic reproduction number R0, is obtained that determines the status of the disease, whether it dies out or persists in the whole population. The model's analysis shows that two equilibria exist, namely, disease‐free equilibrium (DFE) and endemic equilibrium (EE). The global stability of the equilibria is determined using a Lyapunov functional approach. The disease status can be verified based on obtained threshold quantity R0. If R0<1, then DFE is globally stable, leading to eradicating the population's disease. If R0>1, a unique EE exists, and that is globally stable under certain conditions in the feasible region. The Caputo type fractional derivative is taken as the fractional operator. The bifurcation and sensitivity analyses are also performed for the proposed model that determines the relative importance of the parameters in disease transmission. The numerical solution of the model is obtained by the generalized Adams–Bashforth–Moulton method. Finally, numerical simulations are performed to illustrate and verify the analytical results. From the obtained results, it is concluded that the order of the fractional derivative plays a significant role in the dynamic process. Also, from the sensitivity analysis results, it is seen that the parameter δ (infection rate) is positively correlated to R0, while the parameter μ (inhibition rate) is negatively correlated to R0, which means these parameters are more sensitive than others in disease dynamics. [ABSTRACT FROM AUTHOR]

Tile industry wastewater is known to contain a high concentration of TSS and turbidity resulting from various raw materials. In the present study, the effectiveness of the coagulation process on turbidity and TSS removal from Kuwait ceramic tile industry wastewater was investigated using ferric chloride as a coagulant. The experiments were conducted using jar tests to determine the optimum operating conditions of coagulant dosages, pH, and settling time. It was found that the coagulant dosage and medium pH greatly affect the efficiency of the coagulation process. A gradual increase in coagulant dosage from 10 to 50 mg/L increased the efficiency of turbidity removal from 95.6% to 99.5%. The efficiency of the coagulation process was also found to be dependent on pH values, where higher pH improved the efficiency of turbidity removal. It was found that a medium pH of 10, 1 h settling time, and 50 mg/L of coagulant dosage are the optimum process conditions to achieve almost complete removal of turbidity (99.5%) and TSS (99.8%). This study concluded that coagulation might be useful as a primary wastewater treatment process for tile industry wastewater. [ABSTRACT FROM AUTHOR]

COVID-19 disease, a deadly pandemic ravaging virtually throughout the world today, is undoubtedly a great calamity to human existence. There exists no complete curative medicine or successful vaccines that could be used for the complete control of this deadly pandemic at the moment. Consequently, the study of the trends of this pandemic is critical and of great importance for disease control and risk management. Computation of the basic reproduction number by means of mathematical modeling can be helpful in estimating the potential and severity of an outbreak and providing insightful information which is useful to identify disease intensity and necessary interventions. Considering the enormity of the challenge and the burdens which the spread of this COVID-19 disease placed on healthcare system, the present paper attempts to study the pattern and the trend of spread of this disease and prescribes a mathematical model which governs COVID-19 pandemic using Caputo type derivative. Local stability of the equilibria is also discussed in the paper. Some numerical simulations are given to illustrate the analytical results. The obtained results shows that applied numerical technique is computationally strong for modeling COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

In this paper, we develop a three-dimensional fractional-order cancer model. The proposed model involves the interaction among tumor cells, healthy tissue cells and activated effector cells. The detailed analysis of the equilibrium points is studied. Also, the existence and uniqueness of the solution are investigated. The fractional derivative is considered in the Caputo sense. Numerical simulations are performed to illustrate the effectiveness of the obtained theoretical results. The outcome of the study reveals that the order of the fractional derivative has a significant effect on the dynamic process. Further, the calculated Lyapunov exponents give the existence of chaotic behavior of the proposed model. Also, it is observed from the obtained results that decrease in fractional-order ρ increases the chaotic behavior of the model. [ABSTRACT FROM AUTHOR]

Optimization for all disciplines is very important and applicable. Optimization has played a key role in practical engineering problems. A novel hybrid meta-heuristic optimization algorithm that is based on Differential Evolution (DE), Gradient Evolution (GE) and Jumping Technique named Differential Gradient Evolution Plus (DGE+) are presented in this paper. The proposed algorithm hybridizes the above-mentioned algorithms with the help of an improvised dynamic probability distribution, additionally provides a new shake off method to avoid premature convergence towards local minima. To evaluate the efficiency, robustness, and reliability of DGE+ it has been applied on seven benchmark constraint problems, the results of comparison revealed that the proposed algorithm can provide very compact, competitive and promising performance. [ABSTRACT FROM AUTHOR]

Abstract: Thermogravimetric analysis of LiAlH4 chemically mixed with different additives is reported for the application of hydrogen storage. Here, we illustrated the dehydrogenation properties of combined LiAlH4/LiNH2 (2:1) mixture and LiAlH4 wet-doped with different transition metals (Sc, Ti, and V) in their chloride forms. Thermal gravimetric analysis of LiAlH4/LiNH2 system released ∼7.9wt.% of hydrogen in three decomposition steps at temperatures between 75 and 280°C under a heating ramp of 5°Cmin−1. The LiAlH4 doped with transition metals showed the decrease of decomposition temperature down to 30–40°C for both 1st and 2nd dehydrogenation steps as compared to as-received LiAlH4. The catalytic activity in lowering the dehydrogenation temperature of LiAlH4 doped with transition metals increases in the order of pure LiAlH4

Abstract: A comparative study of the dehydrogenation of pure, ScCl3-, TiCl3-, VCl3-, and MnCl2-doped sodium alanate is reported. The samples wet-doped with transition metal halides exhibit significant lowering of both first and second dehydrogenation temperatures when compared with the pure sodium alanate. The reduction of the dehydrogenation temperature, ΔT dec, is maximum for the VCl3-doped alanates: 37 and 55°C, respectively, for the decomposition steps yielding Na3AlH6 and NaH. Among the transition metal halides, the order in which the decomposition temperature is lowered is Mn

The study reported CO 2 storage properties of single-walled carbon nanotubes (CNTs) modified by introducing amino groups onto CNT surfaces via a chemical process. Two different approaches were used to produce amino-functionalized nanotubes by adding lithium amide and l-lysine amino acid. Lithium amide was introduced on CNT surfaces, and then, it was further modified by adding amino-moiety (l-lysine amino acid) to obtain multiamino sites on the CNT surface for CO 2 storage. The aminated CNT were followed by CO 2 adsorption experiments, and amino group interactions with CO 2 have helped CNT to achieve higher adsorption capacity. The successful modification of CNTs showed ameliorated CO 2 storage capacity as compared to pristine CNT. The modified CNT possessed free amine groups on the surface, which led to an enhanced CO 2 adsorption capacity. The modified CNT samples were analyzed by X-ray photoelectron spectroscopy, infrared spectroscopy, and X-ray diffraction techniques., Competing Interests: The authors declare no competing financial interest.