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Fe 1-x S, known for its high theoretical capacity, abundant resources, and intrinsic safety, has become a focal point as a universal anode for Li+/Na+/K+ batteries. However, its fast-charging capability is unsatisfactory due to sluggish ion transport rate and low electrical conductivity. Furthermore, its Li+/Na+/K+ storage mechanisms are still unclear. Here, we fabricate a single-crystal Fe 1-x S/N-doped carbon composite nanosheet interwoven structure, in which N-doped carbon layers onto surface of Fe 1-x S nanosheets ameliorate the electrical conduction and the interwoven nanosheets form open pore channels that favor permeation of electrolytes to boost ion transport. In-situ magnetometry reveals that ion-electron decoupling storage and transport occur in two-phase composites of Fe/Li 2 S, Fe/Na 2 S, and Fe/K 2 S, in which Fe phase stores and transports electrons and sulfide phase stores and transports ions in a space-charge form, resulting in extra ion storage and fast ion transport. Consequently, the nanosheet interwoven structure delivers high capacities (1320.1/652.2/350.6 mAh g−1), outstanding fast-charging performances (679.6/295.4/106.4 mAh g−1 at 20 A g−1), and long cycling life over 5000 cycles as Li+/Na+/K+ battery anodes, respectively [Display omitted] • High pressure induces nanosheet interwoven structure of Fe 1-x S/N-doped carbon. • In-situ magnetometry reveals ion-electron decoupling storing in Fe and sulfides. • "Insertion-conversion-space charge" Li/Na/K storage mechanisms are revealed. • The structure shows unprecedented rate performance in Li/Na/K-ion storage. [ABSTRACT FROM AUTHOR]

Artificial downwelling (AD) potentially mitigates oceanic hypoxia by utilizing pipelines or other artificial structures to transport oxygen-rich seawater from the surface to greater depths. However, limited research has focused on determining the discharge parameters for surface waters, which can often rise back to the upper layer or scour the seafloor sediments if discharged at inappropriate parameters. To address this issue, this study proposes a theory for determining the optimal discharge height of oxygen-rich plumes based on their hydrodynamic characteristics. Laboratory experiments were conducted in a linearly stratified flume to validate the theoretical model. The results show that the proposed theory can effectively calculate the important parameters of the AD jet, including the maximum depth, spread depth, and thickness of the intrusion layer. Furthermore, based on the theory of optimal discharge height, this paper provides plume discharge strategies for a typical AD device in field applications to regulate the operating parameters of the AD equipment, which can effectively keep the oxygen-enriched seawater completely in the hypoxic layer, avoid sediment-suspended secondary pollution, and maximize the oxygenation efficiency in different sea conditions. • Hydrodynamic characteristics of artificial downwelling plumes in stagnant linear stratified environments were investigated. • An artificial downwelling plume discharge model for improving efficiency and avoiding sediment suspension was proposed. • Plume discharge configurations were analyzed for varying geometric and operational parameters in stratified environments. [ABSTRACT FROM AUTHOR]

Interface strain can significantly influence the mechanical, electronic and magnetic properties of low-dimensional materials. Here we investigated by scanning tunneling microscopy how the stress introduced by a mismatched interface affects the structure of a growing graphene (Gr) layer on a Ni(100) surface in real time during the process. Strain release appears to be the main factor governing morphology, with the interplay of two simultaneous driving forces: on the one side the need to obtain two-dimensional best registry with the substrate, via formation of moiré patterns, on the other side the requirement of optimal one-dimensional in-plane matching with the transforming nickel carbide layer, achieved by local rotation of the growing Gr flake. Our work suggests the possibility of tuning the local properties of two-dimensional films at the nanoscale through exploitation of strain at a one-dimensional interface. Image 1 • In-plane graphene - nickel carbide interface on Ni(100). • Real-time imaging of graphene growth at the in-plane interface with nickel carbide. • Strain release during the in-plane growth at the graphene-carbide interface. • Strain-induced modification of graphene lattice corrugation and orientation. [ABSTRACT FROM AUTHOR]

An operando investigation of graphene growth on (100) grains of polycrystalline nickel (Ni) surfaces was performed by means of variable-temperature scanning tunneling microscopy complemented by density functional theory simulations. A clear description of the atomistic mechanisms ruling the graphene expansion process at the stepped regions of the substrate is provided, showing that different routes can be followed, depending on the height of the steps to be crossed. When a growing graphene flake reaches a monoatomic step, it extends jointly with the underlying Ni layer; for higher Ni edges, a different process, involving step retraction and graphene landing, becomes active. At step bunches, the latter mechanism leads to a peculiar 'staircase formation' behavior, where terraces of equal width form under the overgrowing graphene, driven by a balance in the energy cost between C–Ni bond formation and stress accumulation in the carbon layer. Our results represent a step towards bridging the material gap in searching new strategies and methods for the optimization of chemical vapor deposition graphene production on polycrystalline metal surfaces. Image 1 [ABSTRACT FROM AUTHOR]

The improvement of combustion diagnostics was an important basis for developing combustion-related research and technologies. Based on the flame image as the carrier, this work proposed a novel combustion diagnostic technique for the identification of chemical source information through the analysis of abundant flame features contained in the image using a random forest algorithm. Five types of flames under 16 reaction conditions were adopted as experimental cases to examine the accuracy of the proposed technique. Results indicated that the random forest algorithm could well "learn" the correlation mechanism between flame features and chemical source information, and identify the fuel type and reaction condition of unknown flame according to this mechanism. For identifying the fuel type, the accuracy on ethylene, 20 % ethyl acetate, 40 % ethyl acetate, 20 % ethyl butyrate, and 40 % ethyl butyrate doped flames reached 86.2 %, 84.4 %, 100 %, 63.6 %, and 64.3 %, respectively. For identifying the reaction condition, the mean absolute error, max error, and mean absolute percentage error between the predicted O 2 content and the actual value were 0.96 %, 2.53 %, and 3.46 %, respectively. Moreover, the feature analysis result indicated that the importance degree of each feature was not equivalent between the different identification assignments. The flame features such as rectangularity and the variance of G and B in the blue region were the key features for identifying the fuel type. However, the variance of R and R/B of the blue region played a significant role in identifying the reaction condition. [ABSTRACT FROM AUTHOR]

Highlights • UHV-compatible sputter deposition of ZrO 2 leads to clean and flat ZrO 2 films. • The creation of a thin monoclinic ZrO 2 film is reported for the first time. • Tetragonal ZrO 2 films can be prepared and atomically resolved with STM. • Below 5 ML, the structures are influenced by the Rh(111) substrate. • STM indicates positive charge at grain boundaries, which can impede oxygen transport. Abstract We have studied zirconia films on a Rh(111) substrate with thicknesses in the range of 2–10 monolayers (ML) using scanning tunneling microscopy (STM) and low-energy electron diffraction (LEED). Zirconia was deposited using a UHV-compatible sputter source, resulting in layer-by-layer growth and good uniformity of the films. For thicknesses of 2–4 ML, a layer-dependent influence of the substrate on the structure of the thin films is observed. Above this thickness, films show a (2 × 1) or a distorted (2 × 2) surface structure with respect to cubic ZrO 2 (111); these structures correspond to tetragonal and monoclinic zirconia, respectively. The tetragonal phase occurs for annealing temperatures of up to 730 °C; transformation to the thermodynamically stable monoclinic phase occurs after annealing at 850 °C or above. High-temperature annealing also breaks up the films and exposes the Rh(111) substrate. We argue that the tetragonal films are stabilized by the interface to the substrate and possibly oxygen deficiency, while the monoclinic films are only weakly defective and show band bending at defects and grain boundaries. This observation is in agreement with positive charge being responsible for the grain-boundary blocking effect in zirconia-based solid electrolytes. Our work introduces the tetragonal and monoclinic 5 ML-thick ZrO 2 films on Rh(111) as a well-suited model system for surface-science studies on ZrO 2 , as they do not exhibit the charging problems of thicker films or the bulk material and show better homogeneity and stability than the previously-studied ZrO 2 /Pt(111) system. Graphical abstract Image, graphical abstract [ABSTRACT FROM AUTHOR]

Interaction with the substrate strongly affects the electronic/chemical properties of supported graphene. So far, graphene grown by chemical vapor deposition (CVD) on catalytic single crystal transition metal surfaces - mostly 3-fold close-packed - has mainly been studied. Herein, we investigated CVD graphene on a polycrystalline nickel (Ni) substrate, focusing in particular on (100) micrograins and comparing the observed behavior with that on single crystal Ni(100) substrate. The symmetry-mismatch leads to moiré superstructures with stripe-like or rhombic-network morphology, which were characterized by atomically-resolved scanning tunneling microscopy (STM). Density functional theory (DFT) simulations shed light on spatial corrugation and interfacial interactions: depending on the misorientation angle, graphene is either alternately physi- and chemisorbed or uniformly chemisorbed, the interaction being modulated by the (sub)nanometer-sized moiré superstructures. Ni(100) micrograins appear to be a promising substrate to finely tailor the electronic properties of graphene at the nanoscale, with relevant perspective applications in electronics and catalysis. [ABSTRACT FROM AUTHOR]

The potential of artificial upwelling in stimulating seaweed growth, consequently enhancing ocean carbon sequestration has been gaining increasing attention in recent years. This has led to the development of the first solar-powered and air-lifted artificial upwelling system (AUS) in China. However, effective scheduling of the air injection system and energy storage system in dynamic marine environments remains a crucial challenge in the operation of the AUS, as it holds the potential to significantly improve system performance. To tackle this challenge, we propose a novel energy management approach that utilizes the deep reinforcement learning (DRL) algorithm to determine the optimal operational parameters of the AUS at each time interval. Specifically, we formulate the energy optimization problem as a Markov decision process and integrate the quantile network in distributional reinforcement learning with the deep dueling network to solve the problem. Through extensive simulations, we evaluate the performance of our algorithm and demonstrate its superior effectiveness over traditional rule-based approaches and other DRL algorithms in enhancing energy utilization while ensuring the secure and reliable operation of the AUS. Our findings suggest that a DRL-based approach offers a promising way to provide valuable guides for the operation of the AUS and enhance the sustainability of seaweed cultivation and carbon sequestration in the ocean. • DRL algorithm for optimal energy management: Maximizes nutrient transport and ensures system safety. • Improved convergence and robustness: Combines deep quantile networks with deep dueling network architectures. • Extensive simulations validate the proposed solution: Outperforms traditional methods by 20% in system performance. • Insightful analytical results: Guides AUS efficient operation in assisting seaweed cultivation and improving carbon sinks. [ABSTRACT FROM AUTHOR]

• 5-Fluorouracil (5-FU), identified via high-throughput screening, is a potential meropenem adjuvant • 5-FU boosts meropenem against both metallo- (NDM and IMP) and serine (KPC and OXA) β-lactamase-producing bacteria. • 5-FU increased bacterial metabolism and inhibited bla NDM-5 expression to restore meropenem sensitivity. • Combining 5-FU with meropenem increased mouse survival rates to 83.3%, compared with 16.7% with meropenem alone. The global increasing incidence of clinical infections caused by carbapenem-resistant Gram-negative pathogens requires urgent and effective treatment strategies. Antibiotic adjuvants represent a promising approach to enhance the efficacy of meropenem against carbapenem-resistant bacteria. This study shows that the anticancer agent 5-fluorouracil (5-FU, 50 µM) significantly reduced the minimum inhibitory concentration of meropenem against bla NDM-5 positive Escherichia coli by 32-fold through cell-based high-throughput screening. Further pharmacological studies indicated that 5-FU exhibited potentiation effects on carbapenem antibiotics against 42 Gram-negative bacteria producing either metallo-β-lactamases (MBLs), such as NDM and IMP, or serine β-lactamases (Ser-BLs), like KPC and OXA. These bacteria included E. coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter spp. , 32 of which were obtained from human clinical samples. Mechanistic investigations revealed that 5-FU inhibited the transcription and expression of the bla NDM-5 gene. In addition, 5-FU combined with meropenem enhanced bacterial metabolism, and stimulated the production of reactive oxygen species (ROS), thereby rendering bacteria more susceptible to meropenem. In a mouse systemic infection model, 5-FU combined with meropenem reduced bacterial loads and effectively elevated the survival rate of 83.3%, compared with 16.7% with meropenem monotherapy. Collectively, these findings indicate the potential of 5-FU as a novel meropenem adjuvant to improve treatment outcomes against infections caused by carbapenem-resistant bacteria. [Display omitted] [ABSTRACT FROM AUTHOR]

Under near-ambient pressure conditions, carbon monoxide molecules intercalate underneath an epitaxial graphene monolayer grown on Ni(111), getting trapped into the confined region at the interface. On the basis of ab-initio density functional theory calculations, we provide here a full investigation of the intercalated CO pattern, highlighting the modifications induced on the graphene electronic structure. For a CO coverage as low as 0.14 monolayer (ML), the graphene layer is spatially decoupled from the metallic substrate, with a significant C 1s core level shift towards lower binding energies. The most relevant signature of the CO intercalation is a clear switching of the graphene doping state, which changes from n-type, when strongly interacting with the metal surface, to p-type. The shift of the Dirac cone linearly depends on the CO coverage, reaching about 0.9 eV for the saturation value of 0.57 ML. Theoretical predictions are compared with the results of scanning tunnelling microscopy, low-energy electron diffraction and photoemission spectroscopy experiments, which confirm the proposed scenario for the nearly saturated intercalated CO system. This result opens the way to the application of the graphene/Ni(111) interface as gas sensor to easily detect and quantify the presence of carbon monoxide. [Display omitted] • Carbon monoxide intercalated at Graphene/Ni(111) interface forms periodic patterns. • Graphene decouples from Ni(111) after intercalation of carbon monoxide. • CO intercalated at Graphene/Ni(111) interface switches the Graphene doping state. • CO intercalated at Graphene/Ni(111) interface shifts the Dirac cone up to about 1 eV. • Graphene/Ni(111) interface can be used as gas sensor for carbon monoxide. [ABSTRACT FROM AUTHOR]