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Drinking water treatment residues (DWTR) have been regarded as a promising adsorbent for phosphorus control. The granulation of DWTR is a crucial step for its application in the filtration system. Traditional granulation processes could not achieve the balance between stable structures and adsorption capacities. Encapsulation of DWTR powders into alginate beads overcame these drawbacks. However, previous studies ignored the effect of preparation parameters on the properties of DWTR particles. In this study, the effects of sodium alginate (SA) concentrations, alginate types, Fe3+ concentrations, and gelation times on structures and mechanical stabilities of DWTR granules were investigated in depth based on their morphologies and pore structures, and compressive strength. The results showed that SA concentrations influenced the viscosity of DWTR-SA solution, and that granulation of DWTR with low SA concentration resulted in incomplete crosslinking, but granulation of DWTR with high SA concentration could change the shape of final granules. 2% SA was chosen as an optimum concentration for DWTR granules preparation. The ratios of M/G in SA affected the microstructures and mechanical strength of resultant granules. The presence of high G-block content in SA resulted in the formation of a dense crosslinking structure, which increased mechanical strength but decreased specific surface area. The morphologies of DWTR granules did not change as Fe3+ concentrations increased, and the granules with excellent mechanical strength were obtained at FeCl 3 concentrations of 2% (w / v). The DWTR spheres could maturate quickly and are stable after 4 h. The resulting granular DWTR exhibited a comparable P adsorption capacity (26.89 mg-P/g) to the original powder, which was better than traditional P adsorption materials and pellet DWTR produced by high-temperature calcination. The results should be helpful for engineers to choose the best granulation parameters for their applications. [Display omitted] • A detailed parametric study of the DWTR granulated by alginate is performed. • The optimal DWTR granulation parameters are obtained. • Alginate entrapment can balance the diffusion property and stability of granules. • The functional properties of granules can be regulated by preparation parameters. [ABSTRACT FROM AUTHOR]

In the process of coal seam mining, there are often hard thick key layers in the overlying strata. Due to the high strength and good integrity of the hard thick key layer, after the hard thick key layer is broken, the overlying strata will collapse and lose stability in a large area, which is very easy to induce dynamic disasters such as rock burst, mine earthquake, coal wall caving, and roof slab caving. Aiming at the hard and thick key layer overlying the working face, the dynamic response of the mine under the strong mine earthquake induced by the breaking of the main key layer of high-level magmatic rock is numerically simulated and analyzed by using FLAC2D numerical simulation software, and the variation laws of the stress field, displacement field, and velocity field of the coal seam roadway under different boundary conditions and different focal heights are studied. The research shows that the roof of solid coal roadway is prone to vibration in a small range, and the displacement increases and decreases with the disturbance. The displacement of the floor and two sides of the solid coal roadway and the top floor and two sides of the roadway along the goaf continues to increase in the initial stage of the disturbance, and the displacement will remain stable with the continuation of the disturbance. The displacement of both sides and roof and floor of gob roadway can reach stability in the later stage of disturbance, and with the increase of the number of adjacent goaf, the longer it takes for the displacement of surrounding rock to reach stability. When the focal height is lower than 90 m, the variation of surrounding rock response increases sharply with the decrease of focal height. When a strong earthquake occurs in the low rock stratum, the impact damage of roadway surrounding rock is almost inevitable. The influence degree of strong earthquake on the stability of roadway surrounding rock is arranged as follows: gob-side roadway (mined out on one side) > solid coal roadway (mined out on both sides) > solid coal roadway (mined out on one side). The evolution process also shows that the working face boundary conditions have an important influence on the energy propagation of mine earthquake. With the increase of the number of adjacent goafs, the faster the energy attenuation rate of mine earthquake propagation is. The research results have important reference significance for the safe mining of working face under similar geological conditions. [ABSTRACT FROM AUTHOR]

Soil salinity is a growing problem in agriculture, plant growth regulators (PGRs) can regulate plant response to stress. The objective of this study was to evaluate the effects of exogenous 6-benzyladenine (6-BA) on photosynthetic capacity and antioxidant defences in watermelon (Citrullus lanatus L.) seedlings under NaCl stress. Two watermelon genotypes were subjected to four different treatments: (1) normal water (control); (2) 20 mg L−1 6-BA; (3) 120 mmol L−1 NaCl; and (4) 120 mmol L−1 NaCl + 20 mg L−1 6-BA. Our results showed that NaCl stress inhibited the growth of watermelon seedlings, decreased their photosynthetic capacity, promoted membrane lipid peroxidation, and lowered the activity of protective enzymes. Additionally the salt-tolerant Charleston Gray variety fared better than the salt-sensitive Zhengzi NO.017 variety under NaCl stress. Foliar spraying of 6-BA under NaCl stress significantly increased biomass accumulation, as well as photosynthetic pigment, soluble sugar, and protein content, while decreasing malondialdehyde levels, H2O2 content, and electrolyte leakage. Moreover, 6-BA enhanced photosynthetic parameters, including net photosynthetic rate, stomatal conductance, intercellular CO2 concentration, and transpiration rate; activated antioxidant enzymes, such as superoxide dismutase, catalase, and peroxidase; and improved the efficiency of the ascorbate-glutathione cycle by stimulating glutathione reductase, dehydroascorbate reductase, and monodehydroascorbate reductase, as well as ascorbic acid and glutathione content. Principal component analysis confirmed that 6-BA improved salt tolerance of the two watermelon varieties, particularly Zhengzi NO.017, albeit through two different regulatory mechanisms. In conclusion, 6-BA treatment could alleviate NaCl stress-induced damage and improve salt tolerance of watermelons by regulating photosynthesis and osmoregulation, activating the ascorbate-glutathione cycle, and promoting antioxidant defences. The antioxidant and ascorbate-glutathione cycle of two types of salt-tolerant watermelon (Citrullus lanatus L.) seedlings under NaCl stress reveal an cytokinin regulated watermelon acclimation mechanism to the NaCl stress. [ABSTRACT FROM AUTHOR]

In many mining areas, there is a lot of pressed coal under buildings, railways, and water bodies, and there are geological conditions of thick unconsolidated layers, so the surface subsidence has certain particularity. The key to solve the problem of pressed coal is the control technology of surface subsidence. The development of strip filling technology provides a kind of economical and effective surface subsidence control technology. With the passage of time, the natural weathering, flow, and fracture of some coal pillars may lead to the instability and failure of some coal pillars. Therefore, the selection of filling parameters plays an important role in the stability of coal pillars. In order to study the influence factors of surface movement and deformation, considering the influence factors of filling rate, key layer thickness, filling body strength, and unconsolidated layer thickness, FLAC 3D was used to simulate the surface movement deformation, and the orthogonal test method was used to analyze the simulation results, and the sensitivity of the main control factors affecting the surface deformation affected by strip filling mining was studied. The results show that the order of importance of the four factors on the four surface movement and deformation parameters is filling rate > key layer thickness > filling body strength > unconsolidated layer thickness. The influence of these four factors on the surface movement and deformation parameters is gradually decreasing, but the influence degree of different factors has drawn a certain gradient. [ABSTRACT FROM AUTHOR]

At the present time, it is of major significance to study the solid-liquid-gas three-phase coupling relationship of coal, water, and gas in deep-mining stopes in order to prevent and control coal and gas outbursts in high-gas mines. In this study, the influence rules of water on the mechanical characteristics of coal, as well as gas diffusion and migration processes, was examined by combining theoretical analysis and laboratory testing procedures. The results showed that with increases in water content, the mechanical characteristics of coal bodies presented change trends of first increasing and then decreasing. In this study, it was found that the water content levels which corresponded to the maximum shear strength of the coal in the No. 8 coal seam in the study area had ranged between 6.77% and 11.9%, and the water content level corresponding to the extreme point was 8.66%. It was observed that under different water content conditions, the gas desorption speeds of the coal bodies gradually decreased over time. The gas desorption speeds rapidly decreased during the initial desorption stage and then gradually decreased over time. Furthermore, under the different water content conditions, the amount of gas desorption in the coal bodies was observed to gradually increase over time, with the initial desorption amounts displaying rapid increases. Then, with the passage of time, the increase speeds of the gas desorption amount gradually decreased and finally tended to remain at a stable value. It was found that with the increases in water content, the desorption speeds, initial desorption speeds, and desorption amount of gas in the coal bodies continuously decreased. In other words, the water content levels in the coal bodies were negatively correlated with the gas desorption speeds and desorption amounts of the coal bodies. In addition, the gas desorption speeds, initial desorption speeds, and desorption amounts were observed to change more sharply with the increases in water content. The results of this research hold important guiding significance for the improvement of the understanding of the mechanical properties of high-gas coal seams and the implementation of effective gas control measures. [ABSTRACT FROM AUTHOR]

The integration of unique characteristics of nanomaterials with highly specific recognition elements, such as biomolecules and organic molecules, are the foundation of many novel nanoprobes for bio/chemical sensing and imaging. In the present report, branched polyethylenimine (PEI) was grafted with 8-chloroacetyl-aminoquinoline to synthesize a water-soluble and biocompatible quinoline-based Zn2+ probe PEIQ. Then the PEIQ was covalently conjugated to [Ru(bpy)3]2+-encapsulated SiNPs to obtain the ratiometric fluorescence nanoprobe which exhibits a strong fluorescence emission at 600nm and a negligible fluorescence emission at 500nm in the absence of Zn2+ upon a single wavelength excitation. After the addition of different amounts of Zn2+, the fluorescence intensity at 500nm increased continuously while the fluorescence intensity at 600nm remained stable, thus changing the dual emission intensity ratios and displaying continuous color changes from red to green which can be clearly observed by the naked eye. The nanoprobe exhibits good water dispersivity, biocompatibility and cell permeability, high selectivity over competing metal ions, and high sensitivity with a detection limit as low as 0.5µM. Real-time imaging of Zn2+ in A549 cells has also been realized using this novel nanoprobe. [ABSTRACT FROM AUTHOR]

Abstract: Glutathione (GSH) plays key roles in biological systems and serves many cellular functions. Since biothiols all incorporate thiol, carboxylic and amino groups, discriminative detection of GSH over cysteine (Cys) and homocysteine (Hcy) is still challenging. We herein report a dual-mode nanosensor with both colorimetric and fluorometric readout based on carbon quantum dots and gold nanoparticles for discriminative detection of GSH over Cys/Hcy. The proposed sensing system consists of AuNPs and fluorescent carbon quantum dots (CQDs), where CQDs function as fluorometric reporter, and AuNPs serve a dual function as colorimetric reporter and fluorescence quencher. The mechanism of the nanosensor is based on two distance-dependent phenomenons, color change of AuNPs and FRET. Through controlling the surface properties of as-prepared nanoparticles, the addition of CQDs into AuNPs colloid solution might induce the aggregation of AuNPs and CQDs, leading to AuNPs color changing from red to blue and CQDs fluorescence quench. However, the presence of GSH can protect AuNPs from being aggregated and enlarge the inter-particle distance, which subsequently produces color change and fluorescent signal recovery. The nanosensor described in this report reflects on its simplicity and flexibility, where no further surface functionalization is required for the as-prepared nanoparticles, leading to less laborious and more cost-effective synthesis. The proposed dual-mode nanosensor demonstrated highly selectivity toward GSH, and allows the detection of GSH as low as 50nM. More importantly, the nanosensor could not only function in aqueous solution for GSH detection with high sensitivity but also exhibit sensitive responses toward GSH in complicated biological environments, demonstrating its potential in bioanalysis and biodection, which might be significant in disease diagnosis in the future. [Copyright &y& Elsevier]

Product prices fluctuate dynamically with changes in market supply and demand. This poses a dilemma for dealers, that is, dealers need to establish a dynamic extended warranty (EW) pricing strategy based on the fluctuations in product prices to attract consumers. To address this challenging issue, we establish a dynamic integration model to derive optimal product prices and two-dimensional (2D) EW prices in a multistage dynamic market environment to maximize the dealer's expected discounted profit during the product life cycle. In order to explore the dynamic influence mechanism between reliability engineering factors and market elements, this model combines the warranty cost model influenced by reliability related repair learning characteristics and the 2D EW demand model influenced by product price fluctuations. The model allows dealers to identify the relationships among various factors, including repair learning characteristic, production scale effect, product cost, EW cost in product reliability level, and fluctuating product demand and EW demand in market demand level, and more important, their effects, on the dealers' profit. The necessary optimality conditions and case study are conducted for static and dynamic markets. • Dynamic integration pricing model of two-dimensional extended warranty is proposed. • The effects of product price fluctuations and repair learning are incorporated. • Buyer's sensitive tendency affects the pricing of products and extended warranty. • Dynamic pricing of extended warranty profits more than a static pricing strategy. • Dealers need to cultivate repair learning ability to generate greater profits. [ABSTRACT FROM AUTHOR]