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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]

The increasing demand for gold because of its high market price and its wide use in the electronic industry has attracted interest in gold recovery from electronic waste (e-waste). Gold is being dumped as solid e-waste which contains gold concentrations ten times higher than gold ores. Adsorption is a widely used approach for extracting gold from e-waste due to its simplicity, low cost, high efficiency, and reusability of adsorbent material. Natural polysaccharides received increased attention due to their natural abundance, multi-functionality, biodegradability, and nontoxicity. In this review, a brief history, and advancements in this technology were evaluated with recent developments in the preparation and mechanism advancements of natural polysaccharides for efficient gold recovery. Moreover, we have discussed some bifunctional modified polysaccharides with detailed gold adsorption mechanisms. The modified adsorbent materials developed from polysaccharides coupled with inorganic/organic functional groups would demonstrate an efficient technology for the development of new bio-based materials for efficient gold recovery from e-waste. Also, future views are recommended for highlighting the direction to achieve fast and effective gold recovery from e-waste in a friendly and sustainable manner. [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

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]

Abstract: Hydrogen adsorption studies of silver-embedded carbon nanotubes (Ag/CNTs) synthesized by in situ reduction method were performed at 298K and hydrogen equilibrium pressure of 23atm. The saturated reversible hydrogen storage capacity exhibited by silver embedded carbon nanotubes is found to be 0.86wt.% which is nearly 40% more as compared to the hydrogen uptake of purified carbon nanotubes measured under similar experimental conditions. The enhanced hydrogen storage capacity of carbon nanotubes is attributed to the spillover of physisorbed hydrogen from silver nanoparticles. The hydrogen uptake by Ag/CNT samples follows the Henry’s rule, suggesting that there is no significant adsorbate–adsorbate interaction in the low-pressure region. XRD spectrum indicated that 32% increase in particle size was observed in hydrogenated samples as compared to non-hydrogenated samples. [Copyright &y& Elsevier]

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 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]

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]

The interfacial properties of carbon fibers (CFs) composites were improved by modifying the self-emulsifying amphiphilic epoxy sizing agent with nano-SiO 2 particles. Herein, a series of inorganic–organic nano-SiO 2 core-cationic epoxy shell hybrid sizing agents (referred to as nano-SiO 2 core–shell hybrid sizing agents) with various nano-SiO 2 contents were synthesized and used to enhance the mechanical properties of CF/EP. The study indicated that the nano-SiO 2 core–shell hybrid sizing agents had the characteristics of the perfect core–shell structure, single dispersion, particle sizes controllable, good storage and high heat resistance. Nano-SiO 2 core–shell hybrid sizing agents significantly increased the surface roughness and the surface energy of CFs compared to the unmodified sizing agent. Nano-SiO 2 core–shell hybrid sizing agents (7.2% SiO 2) increased ILSS, IFSS by 16.92%, 21% and nano-SiO 2 core–shell hybrid sizing agents (5.8% SiO 2) increased tensile force of monofilament CF by 23.78%, respectively, compared with the unmodified agent. These reinforcements may have been caused by the enhancement of the stress transference of nano-particles in the interface between CFs and EP through an interlocking mechanism. As a result, the nano-SiO 2 core–shell sizing agent overcomes the lack of adhesion of traditional nano modification methods and shows remarkable adhesion properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • Revealing the interactions between triazinedithiol groups and heavy metal ions. • Triazinedithiol-functionalized materials are far superior to the traditional ones. • Triazinedithiol-functionalized adsorbent can highly remove Cd(II). • Triazinedithiol-functionalized support can highly disperse Ag, Pd, and Ni. • Triazinedithiolsilane could replace conventional mercapto silanes in the future. Effective bonding interactions between various organo-functional groups and metals can contribute to novel materials or fancy performances. In order to reveal the superiority of triazinedithiolsilanes with di-sulfydryl groups over the conventional mercapto silanes with mono-sulfydryl, and amino silanes with mono-amine, for the first time, the above three silanes have been chemically anchored onto cutting-edge dendritic mesoporous silica nanospheres (DMSNs) for performance comparison. The three composite materials have been designed to serve as not only the adsorbents to remove heavy metal cadmium Cd(II), but also the catalyst-supports to load and disperse metal (noble metal Ag, Pd, and base metal Ni) nanoparticles (NPs). The abilities of triazinedithiol-functionalized DMSNs are far superior to the other two specimens both in Cd(II) capture and metal dispersion, owing to the specific nature of triazinedithiol group. The q e values of triazinedithiol-, mercapto-, and amino-functionalized DMSNs can reach to 1280, 816, 900 mg/g, respectively. Moreover, triazinedithiol-functionalized DMSNs could disperse metal NPs more uniformly that the conventional silane-modified ones. It is expected that triazinedithiolsilane compounds could faultlessly replace conventional mercapto silanes in some practical application fields and would shine brilliantly in the future. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cs based functionalized microspheres as adsorbents were developed. • In situ crosslinking between Cs and FTn were carried out. • Effect of proportion of FTn on uranium(VI) adsorption were studied. • Uranium(VI) removal from seawater using CsFTnCM was promising. • Seawater exposed CsFTnCM2 showed best uranium(VI) desorption. The seawater contains 4.5 billion tons of uranium(VI), which is quite enough to provide a continuous supply of infinite nuclear energy. However, it is a sudden need to develop adsorbents from abundant available source, easy collect property, large durability and high uranium(VI) adsorption capacity from seawater. In this work, a single-step process was developed for the preparation of chitosan (Cs) functionalized tubular carbon nanocomposite microspheres (CsFTnCM) for efficient uranium(VI) adsorption from seawater. The application of newly synthesized adsorbent for uranium(VI) removal from seawater is explored. Thus prepared adsorbent (CsFTnCM2) is found to adsorb 99.5% uranium(VI) from seawater. The CsFTnCM2 (Cs/FTn,1:1) comprising NH 2 and COOH content approximately 0.61 mmol/g and 0.23 mmol/g, respectively. This kind of adsorbent possessed a uranium(VI) loading capacity of 0.660 (mg/g) from seawater. The adsorption kinetics not only dependent on the physical structure of the adsorbent but depends on the proportion of FTn in the Cs-matrix. However, the kinetics of uranium(VI) adsorption was increased by increasing the content of FTn up to a certain limit. The adsorption efficiency of uranium(VI) was not affected by the presence of coexisted ions, whose concentration is 1000 times greater than uranium(VI) in seawater. The desorption of uranium(VI) from the seawater exposed adsorbents were investigated and the results showed the uranium(VI) strip from the adsorbents found to be efficiently using Na 2 CO 3. [ABSTRACT FROM AUTHOR]

Abstract: Hydrogen uptake of Pt–Pd alloy decorated MWCNTs was performed under ambient temperature and moderate pressures. Nanocrystalline alloy is coated on the MWCNTs via thermal vapour deposition (TVD) method. The size of the Pt–Pd alloy decorated by TVD on MWCNTs is 5nm. The maximum reversible hydrogen storage exhibited by nanocomposite, measured at 298K and pressure of 20atm is found to be ∼2.0wt.%, which is nearly 3 times more as compared to pristine CNTs performed under similar experimental conditions. The improvement of hydrogen storage in coated sample as compared to pristine CNTs is due to the spillover of physisorbed hydrogen from the alloy nanoparticles to the CNTs. [Copyright &y& Elsevier]

[Display omitted] • POP-F structure was developed by free radical polymerization method. • Amidoxime modified POP-F material showed selective U(VI) adsorption. • POP-AOF shows fast and efficient U(VI) adsorption from natural seawater. • The adsorption capacity of POP-F and POP-AOF are 149.1 ± 0.2 and 500.1 ± 0.5 mg/g. Simple and facile technologies for efficient uranium(VI) removal from seawater is highly interesting for energy and environmental sustainability. By take advantage of the polymerization of acrylonitrile, amidoxime modified porous organic polymer flower-like structure (POP-AOF) adsorbent is synthesized. POP-AOF is of great interest for energy and environmental applications, since their unique structures not only provides high functionality but also accelerates high selectivity via secondary building units. The unique structure of POP-AOF showed multistep kinetics controlled by chemisorption and intraparticle diffusion model. In practical applications, POP-AOF performed as an efficient adsorbent for selective uranium(VI) removal from simulated solution and seawater are investigated. Time-dependent measurement of uranium(VI) adsorption capacity and half-saturation time of seawater exposed POP-AOF is analyzed using a one-site ligand saturation model. The coordination was analyzed by spectroscopic analysis and amidoxime groups of POP-AOF act as a bidentate ligand to trap uranium(VI) from seawater. This work addresses the potential of acrylonitrile and amidoxime chemistry for the development of new adsorbents for efficient uranium(VI) removal from seawater. [ABSTRACT FROM AUTHOR]

Abstract: We examined the hydrogen adsorption of palladium-embedded carbon nanotubes (CNTs) under ambient temperature and hydrogen partial pressures: 0.66–2.2MPa. Nano-crystalline palladium is embedded in the MWCNTs via impregnation and in situ reduction reaction. The maximum reversible hydrogen storage exhibited by nanocomposite materials, measured at 298K and 1.6MPa is 0.18wt% which is nearly twice the storage capacity of pristine CNTs. However, the storage capacity of the composite materials is approximately an order less than that of the palladium nanoparticles. The enhanced storage capacity is due to cumulative hydrogen adsorption by CNTs and Pd nanoparticles. We observe no significant difference between the reversible storage capacities of the composites made by two methods, which implies that the storage capacities of the samples essentially depend on the uptake by CNTs. [Copyright &y& Elsevier]