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[Display omitted] • Nitrogen-doped carbon dots (N -CDs) was synthesized from Sanghuangporus lonicericola. • N -CDs possess good water solubility, photostability and high quantum yield of 60.99%. • N -CDs act as optical sensors with high selectivity towards tetracyclines (TCs). • N -CDs detect TCs in aquaculture water and rat serum by internal filtration effect. Tetracyclines (TCs) are a kind of broad − spectrum and effective antibiotics that have been widely used in veterinary and human medicine, which may pose serious risk to human health if they are accumulated in human body. The fluorescence method using nanomaterials as probes has been gradually used for the detection of TCs because of its simple operation, high sensitivity and recognition ability. Herein, a novel nitrogen doped carbon dots (N − CDs) derived from Sanghuangporus lonicericola was synthesized by hydrothermal method. The N − CDs exhibited bright blue fluorescence, high quantum yield (QY) of 60.99 %, and excellent photostability, which was employed as a fluorescent probe for selective detection of TCs, including oxytetracycline (OXY), doxycycline (DOX), tetracycline (TCY) and minocycline (MNO). The fluorescence intensity of the N − CDs decreased linearly with the increasing concentration of OXY, DOX, TCY and MNO, and their concentrations were in the range of 0.6 – 73.3 μM, 0 – 95.2 μM, 6.5 – 72.3 μM and 10 – 52.6 μM, respectively. As for practical application, the as − prepared N − CDs could not only be effectively applied for determination of TCs in aquaculture water and rat serum samples with low relative standard deviation (RSD) and good recoveries, but also track the concentration change of TCs in rats blood model over time. Towards the fluorescence detection mechanism, the results of UV–vis absorption spectra and fluorescence lifetimes proved that the fluorescent quenching of N − CDs occurred from internal filtration effect (IFE) in the presence of TCs. This work provides guidance for the development of new TCs sensors based on fluorescent nanomaterials, and has a good application prospect in the quality control of agriculture, food and pharmaceutical production processes. [ABSTRACT FROM AUTHOR]

Aiming at the challenges to the accurate and stable heading control of underactuated unmanned surface vehicles arising from the nonlinear interference caused by the overlay and the interaction of multi interference, and also the uncertainties of model parameters, a heading control algorithm for an underactuated unmanned surface vehicle based on an improved backpropagation neural network is proposed. Based on applying optimization theory to realize that the underactuated unmanned surface vehicle tracks the desired yaw angle and maintains it, the improved momentum of weight is combined with an improved tracking differentiator to improve the robustness of the system and the dynamic property of the control. A hyperbolic tangent function is used to establish the nonlinear mappings an approximate method is adopted to summarize the general mathematical expressions, and the gradient descent method is applied to ensure the convergence. The simulation results show that the proposed algorithm has the advantages of strong robustness, strong anti-interference and high control accuracy. Compared with two commonly used heading control algorithms, the accuracy of the heading control in the complex environment of the proposed algorithm is improved by more than 50%. [ABSTRACT FROM AUTHOR]

In this paper, a novel dynamic surface sliding mode control (DSSMC) method, combined with a lateral velocity tracking differentiator (LVTD), is proposed for the cooperative formation control of underactuated unmanned surface vehicles (USVs) exposed to complex marine environment disturbances. Firstly, in view of the kinematic and dynamic models of USVs and the design idea of a virtual control law in a backstepping approach, the trajectory tracking control problem of USVs' cooperative formation is transformed into a stabilisation problem of the virtual control law of longitudinal and lateral velocities. Then, aiming at the problem of differential explosion caused by repeated derivation in the process of backstepping design, the first-order low-pass filter about the virtual longitudinal velocity and intermediate state quantity of position is constructed to replace differential calculations during the design of the control law, respectively. In order to reduce the steady-state error when stabilising the virtual lateral velocity control law, the integral term is introduced into the design of the sliding mode surface with a lateral velocity error, and then the second-order sliding mode surface with an integral is structured. In addition, due to the problem of controller oscillation and the role of the tracking differentiator (TD) in active disturbance rejection control (ADRC), the LVTD is designed to smooth the state quantity of lateral velocity. Subsequently, based on the dynamic model of USV under complex marine environment disturbances, the nonlinear disturbance observer is designed to observe the disturbances and compensate the control law. Finally, the whole cooperative formation system is proved to be uniformly and ultimately bounded, according to the Lyapunov stability theory, and the stability and validity of the method is also verified by the simulation results. [ABSTRACT FROM AUTHOR]

This paper focuses on the mechanism of rock cutting with conical picks under different confining pressures. First, the 2-dimensional numerical model of rock cutting with two conical picks is established by particle flow code software. Then, the basic contents of cutting modes, cutting efficiency, optimal cutting space, rock fragmental size and crack growth ability are studied. Finally, the cutting modes are verified by cutting experiments. According to the results, the confining pressure directly affects the crack growth ability, it presents four basic cutting modes for different crack growth abilities, mode a, mode b, mode c and mode d, respectively. And they influence the cutting efficiency, optimal cutting space, cutting force and crack growth ability. At no confining pressure, the optimal cutting space is 70 mm, the optimal cutting space is 90 mm under 5 MPa and 10 MPa conditions. The research can provide some reference and guidance for continuous miner construction in different confining pressure environments. [ABSTRACT FROM AUTHOR]

To obtain a green and cost-effective one-part alkali-activated grouting material (OAGM) with good comprehensive performance for subgrade reinforcement and determine its proper mix parameters. In this study, using response surface methodology (RSM), multiple objective particle swarm optimization (MOPSO) algorithm and the technique for order preference by similarity to an ideal solution (TOPSIS) algorithm coupled with entropy weight method, two multi-objective optimization schemes for OAGM were performed, one only considering performance and another considering performance, embodied CO 2 emission (ECO 2 e) and cost. Then, the correlation-based feature selection (CFS) algorithm was used to evaluate the importance of various molar ratios as mix parameters on the performance of OAGM. Finally, the effects of key mix parameters on the microstructure and reaction products of OAGM were studied. RSM results show that W/S (water to solid) ratio, borax (BR) content and UCG content chiefly govern the flowability, initial setting time and mechanical strength of OAGM respectively, and the interactions between some factors also significantly affect these properties. MOPSO and entropy-TOPSIS algorithm can be used to optimize OAGM objectively. Two optimal OAGM pastes both have better comprehensive performance and much lower ECO 2 e than ordinary Portland cement (OPC) paste. And the optimal OAGM considering performance, ECO 2 e and cost even has 7.68% lower cost than OPC paste. But another optimal OAGM has the best comprehensive performance. CFS results show that the molar ratios of Si/Al, Al/Ca, Na 2 O/H 2 O, B 2 O 3 /CaO and B 2 O 3 /Al 2 O 3 are the key mix parameters of OAGM. Al/Ca rather than Si/Al is the most important mix parameter to the 28-day compressive strength. And higher Si/Al and Al/Ca deteriorates the microstructure and hinders the formation of C-A-S-H gel, while higher Na 2 O/H 2 O has the opposite effect. This study provides guidance for objective optimization and the determination of proper mix parameters of OAGM, and promotes the market-oriented application of OAGM. • Multi-objective optimization was conducted for OAGM using MOPSO and entropy-TOPSIS algorithm. • Key mix parameters of OAGM were determined by CFS algorithm. • The optimal OAGM with low carbon footprint, low cost and good comprehensive performance was obtained. • Quadratic regression equations used for performance prediction of OAGM were obtained by RSM. • Effects of key mix parameters on the microstructure and reaction product of OAGM were characterized. [ABSTRACT FROM AUTHOR]

Synchronous rejuvenation of colloidal structure of bitumen and crosslinking structure of Styrene-butadiene-styrene (SBS) polymer is of great significance for high-quality cycling and reusing aged SBS modified bitumen (SMB) mixture. In this study, a novel reactive warm-mix rejuvenator (RWR) was developed by using 56.4% rubber oil, 24.5% epoxy-terminated polybutadiene ether (ETPBE), 13.8% cardanol (CA), 3.2% modified polyethylene (PE) wax and 2.1% antiaging agent based on uniform design method. Before the RWR preparation, Fourier transform infrared spectroscopy (FTIR) tests were conducted to investigate the repairing effects of ETPBE and CA on fracture crosslinking structure for aged SBS that had been subjected to coupling effect of multiple aging factors. After the optimum technical parameters of rejuvenated SMB were determined, physical properties, high- and low-temperature performances, and fatigue resistance of rejuvenated SMB as well as its molecular structure and microstructure surface were investigated to evaluate the synchronous rejuvenation of RWR on aged SMB. Additionally, warm-mix effect of RWR on construction temperatures of rejuvenated SMB was analyzed through rotational plate viscosity test. Results indicate that both ETPBE and CA can react with oxygen-containing groups in broken molecular chains of aged SBS with the catalysis of 0.1% triethanolamine, which is conducive to reconnecting the fractured SBS polymer segments. RWR is able to regulate the bitumen components and repair the broken SBS molecular chains for aged SMB, which facilitates the reconstruction of crosslinking structure and promotes the surface roughness for rejuvenated SMB. Physical properties, low-temperature rheological performance and fatigue resistance of aged SMB were successfully restored by using the RWR. Considering high-temperature performance of rejuvenated SMB, 12% was recommended as an optimum RWR content to mix with aged SMB at around 155 ℃ for 15 min, which enables rejuvenated SMB to achieve a balanced performance. Compared with construction temperatures of original SMB, mixing and compaction temperatures of rejuvenated SMB using the RWR can be reduced by 29 ℃ and 28 ℃, respectively. This developed RWR is promising to fully regenerate the performances of aged SMB and reduce the construction temperatures in reuse of aged SMB mixtures. • A novel reactive warm-mix rejuvenator was developed through uniform design method. • Degraded crosslinking structure of aged SBS polymer can be repaired by using the RWR. • The RWR can successfully restore performances of aged SBS modified bitumen. • The RWR is able to significantly reduce construction temperatures for rejuvenated SBS modified bitumen. [ABSTRACT FROM AUTHOR]

• A new warm-mix recycling agent was developed using uniform design method. • WR improves low-temperature property and fatigue resistance of reclaimed asphalt. • WR remarkably reduces construction temperatures of reclaimed asphalt. • Compared with commercial rejuvenators, WR exhibits better economical benefit. Warm-mix recycling asphalt mixture has remarkable environmental and economic benefits. In this study, a new warm-mix recycling agent (WR) was developed by using base oil (80%), surfactant (9.5%), plasticizer (8.0%) and antiaging agent (2.5%) based on uniform design method. Experimental tests including penetration, softening point, ductility, elastic recovery, dynamic shear rheometer (DSR), multiple stress creep recovery (MSCR), bending beam rheometer (BBR), linear amplitude sweep (LAS), rotational viscosity as well as Fourier transform infrared spectroscopy (FTIR) test were conducted to evaluate the properties of aged binders incorporating the WR and other two commercial rejuvenators, i.e. an emulsified rejuvenator (ER) and a resinous rejuvenator (RR). Additionally, the workability and cost of reclaimed asphalt binders were analyzed. Results indicate that the WR is able to rejuvenate conventional physical properties of aged asphalt. Reclaimed asphalt containing WR shows the best low-temperature performance and longest fatigue life than that containing other two commercial rejuvenators. With regard to high-temperature performance, reclaimed asphalt incorporating WR compares favorably with that incorporating ER. The results from FTIR test demonstrated that physical interaction dominated the rejuvenation of aged asphalt after adding the WR. WR can significantly replenish the volatiles in aged asphalt, and restore its components' proportion that resembles the virgin asphalt. In comparison with ER and RR, WR exhibits a lower increased cost and the excellent capability of reducing mixing and compaction temperature. [ABSTRACT FROM AUTHOR]

• Activated rubber powder was used to prepare PS-ARP modifier. • PS-ARP was applied to prepare modified asphalt with SBS. • PS-ARP/SBS modified asphalt exhibited better mechanical properties. • PS-ARP added asphalt had better heat and rutting resistance, and viscoelasticity. • Better performance of PS-ARP was due its high-strength composite network with SBS. Activated rubber powder (ARP) was grafted into polystyrene (PS) by in-situ polymerization to obtain PS-ARP which was used as a modifier to prepared styrene–butadienestyrene (SBS) modified asphalt. Three indicators, dynamic shear rheology (DSR), multi-stress creep recovery (MSCR), time scan, bending beam rheology (BBR) and segregation tests results showed that PS-ARP can improve low temperature plasticity, heat resistance, viscoelasticity, anti-rutting, fatigue and low temperature performance of modified asphalt. The addition of 3-PS-ARP improved the ductility of SBS modified asphalt from 13.03 cm to 23.1 cm (5 °C) while fatigue and anti-rutting performance were enhanced about 85.53% (30 °C) and 97.28% (82 °C), respectively. FT-IR and SEM analyses showed successful synthesis of PS-ARP. FM analyses confirmed that large number of PS microspheres were encapsulated on the surface of PS-ARP resulting in a composite network structure with SBS in asphalt. [ABSTRACT FROM AUTHOR]

Enhancing the synergistic interplay between adsorption and catalytic oxidation to amplify Fenton-like effects remains a pivotal challenge in advancing water pollution remediation strategies. In this study, a suite of novel carriers (SH) composed of silica (SiO 2 ) and hydroxyapatite (HAp) in different ratios were synthesized through an amalgamation of the sol-gel and co-precipitation techniques. Notably, various forms of copper (Cu) species, including Cu 2+ ions and Cu nanoclusters (Cu NCs), could be stably incorporated onto the SH surface via meticulous loading and doping techniques. This approach has engendered a new class of Fenton-like catalysts (Cu NCs-SH1-5) characterized by robust acid-base tolerance stability and remarkable recyclability. Compared with the previously reported Cu NCs-HAp, this catalyst with lower Cu species content could achieve better performance in adsorbing and degrading dyes under the aid of hydrogen peroxide (H 2 O 2 ). The catalyst's dual action sites, specifically the adsorption sites (SiOH, POH, slit pores) and catalytic centers (multivalent Cu species), had clear division of labor and collaborate with each other. Further, reactive oxygen species (ROS) identification and astute electrochemical testing have unveiled the mechanism underpinning the cooperative degradation of dyes by three types of ROS, spawned through electron transfer between the Fenton-like catalyst (Cu NCs-SH) and H 2 O 2 . From these insights, the mechanism of synergistic adsorption-catalytic removal was proposed., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Electrochemical CO 2 reduction reaction (ECO 2 RR) with controlled product selectivity is realized on Ag-Cu bimetallic surface alloys, with high selectivity towards C2 hydrocarbons/alcohols (≈60 % faradaic efficiency, FE), C1 hydrocarbons/alcohols (≈41 % FE) and CO (≈74 % FE) achieved by tuning surface compositions and applied potentials. In situ spectral investigations and theoretical calculations reveal that surface-composition-dependent d-band center could tune *CO binding strengths, regulating the *CO subsequent reaction pathways and then the product selectivity. Further adjusting the applied potentials will alter the energy of participated electrons, which leads to controlled ECO 2 RR selectivity towards desired products. A predominant region map, with an indicator proposed to evaluate the thermodynamic predominance of the *CO subsequent reactions, is then provided as a reliable theoretical guidance for the controllable ECO 2 RR product selectivity over bimetallic alloys., (© 2023 Wiley-VCH GmbH.)

Background: Scatophagus argus, an estuarine inhabitant, can rapidly adapt to different salinity environments. However, the knowledge of the molecular mechanisms underlying its strong salinity tolerance remains unclear. The gill, as the main osmoregulatory organ, plays a vital role in the salinity adaptation of the fish, and thus relative studies are constructive to reveal unique osmoregulatory mechanisms in S. argus., Results: In the present study, iTRAQ coupled with nanoLC-MS/MS techniques were employed to explore branchial osmoregulatory mechanisms in S. argus acclimated to different salinities. Among 1,604 identified proteins, 796 differentially expressed proteins (DEPs) were detected. To further assess osmoregulatory strategies in the gills under different salinities, DEPs related to osmoregulatory (22), non-directional (18), hypo- (52), and hypersaline (40) stress responses were selected. Functional annotation analysis of these selected DEPs indicated that the cellular ion regulation (e.g. Na + -K + -ATPase [NKA] and Na + -K + -2Cl - cotransporter 1 [NKCC1]) and ATP synthesis were deeply involved in the osmoregulatory process. As an osmoregulatory protein, NKCC1 expression was inhibited under hyposaline stress but showed the opposite trend in hypersaline conditions. The expression levels of NKA α1 and β1 were only increased under hypersaline challenge. However, hyposaline treatments could enhance branchial NKA activity, which was inhibited under hypersaline environments, and correspondingly, reduced ATP content was observed in gill tissues exposed to hyposaline conditions, while its contents were increased in hypersaline groups. In vitro experiments indicated that Na + , K + , and Cl - ions were pumped out of branchial cells under hypoosmotic stress, whereas they were absorbed into cells under hyperosmotic conditions. Based on our results, we speculated that NKCC1-mediated Na + influx was inhibited, and proper Na + efflux was maintained by improving NKA activity under hyposaline stress, promoting the rapid adaptation of branchial cells to the hyposaline condition. Meanwhile, branchial cells prevented excessive loss of ions by increasing NKA internalization and reducing ATP synthesis. In contrast, excess ions in cells exposed to the hyperosmotic medium were excreted with sufficient energy supply, and reduced NKA activity and enhanced NKCC1-mediated Na + influx were considered a compensatory regulation., Conclusions: S. argus exhibited divergent osmoregulatory strategies in the gills when encountering hypoosmotic and hyperosmotic stresses, facilitating effective adaptabilities to a wide range of environmental salinity fluctuation., (© 2022. The Author(s).)

Selenoprotein K (SELENOK) and Selenoprotein S (SELENOS) are the members of the endoplasmic-reticulum-associated degradation (ERAD) complex, which is responsible for translocating misfolded proteins from the endoplasmic reticulum (ER) to the cytosol for degradation. Besides its involvement in the ERAD, SELENOK was shown to bind and stabilize the palmitoyl transferase DHHC6, and thus contributes to palmitoylation. SELENOK and SELENOS reside in the ER membrane by the way of a single transmembrane helix. Both contain an intrinsically disordered region with a selenocysteine (Sec) located one or two residues away from the C-terminus. Here, we describe the preparation of the Sec-containing forms of SELENOS and SELENOK. SELENOK, which contains no native cysteines, was prepared in an E. coli cysteine auxotroph strain by exploiting the codon and the insertion machinery of Cys for the incorporation of Sec. In contrast, the preparation of SELENOS, which contains functionally important cysteine residues, relied on E. coli's native Sec incorporation mechanism.