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The efficient extraction of uranium, as the primary component of nuclear energy, holds significant implications. Drawing inspiration from the charge interaction observed in biological ion channels, we encapsulated negatively charged polystyrene sulfonate (PSS) or sodium polystyrene carboxylate (PVBA) into the nanochannels of amidoxime functionalized covalent organic framework (COF-AO) in-situto alter the cavity environment of COF-AO. The synthesized COF-AO-PSS and COF-AO-PVBA are used for ultra-fast and highly selective uranium recovery. The negatively charged PSS/PVBA was confined in the COF-AO channel providing the driving force for uranium transport and blocking other ions, thus creating a highly selective “uranium highway”. Additionally, introducing sulfonate groups or carboxyl groups into COF-AO offers supplementary coordination environments and weak interactions with uranium. Due to charge-assisted migration and various interaction mechanisms, both COF-AO-PSS and COF-AO-PVBA exhibit faster adsorption kinetics and higher selectivity compared to COF-AO alone. Their adsorption capacities are 3.8 times and 2.4 times that of COF-AO alone respectively which highlights the necessity for constructing biomimetic ion channels in uranium adsorption processes. This work presents a bionic adsorbent based on covalent organic frameworks (COFs) for the first time, overcoming environmental and equipment limitations associated with traditional photocatalysis and electrocatalysis methods for uranium capture, opening up new avenues for designing multifunctional materials that mimic biological systems.

N,N-Dimethylformamide was reacted with hexamethyldisilazane to generate an N,N-dimethylformimidamide intermediate; thereafter, a reaction with acetophenones/β-diketones was induced to form enaminones. The one-pot synthetic protocol described in this paper can be applied to synthesize 1,4-disubstituted 1,2,3-triazoles and 1,4,5-trisubstituted 1,2,3-triazoles, in which organic azides are used as substrates under optimized conditions. Furthermore, this protocol uses readily available materials, is nearly free of solvent, can be applied to gram-scale operations, and leads to the formation of structurally diverse products with favorable yields.

Co-pyrolysis may enhance the energy efficiency of anaerobic digestion waste (biogas residues), while simultaneously facilitating the clean utilization of coal. A thermogravimetric analyzer (TG), TG-FTIR-MS, and infrared heating technique were employed to investigate the rapid co-pyrolysis properties of long-flame coal (LFC) and biogas residues (BR) in this study. Meanwhile, the effects of temperature on the co-pyrolysis product distributions and compositions were studied in reactors that were heated with electric heating and rapid infrared heating. The co-pyrolysis of LFC and BR had the potential to decrease greenhouse gas emissions, as indicated by the TG-FTIR/MS findings. The co-pyrolysis kinetics were calculated using two models (KAS and FWO); the average Eαvalues are 176.09 and 187.26 kJ/mol, respectively. Tar yields increased initially in IH (electric heating) and EH (infrared heating) reactors, before declining as the temperature rose. The tar yields are greatest for EH at 500 °C (16.12 wt%) and IH at 600 °C (16.02 wt%). Tar yields generated via infrared heating were greatly higher than those generated by EH at 600–700 ℃. IH has a higher tar yield due to the fact that there are significant synergistic effects between coal and lignin, protein, and lipid at high temperatures. The GC-MS results indicate that IH has promoted the aromatization and ketonization reactions. Moreover, more monocyclic aromatic and bicyclic aromatic products are generated by infrared heating, suggesting an indication of tar quality improvement. An elevated co-pyrolysis temperature results in a greater degree of graphitization in char.

The usual linear superconducting resonators (with equal frequency intervals between nearest-neighbor modes) are right-handed electromagnetic devices, wherein cross talks between the nearest-neighbor modes are practically unavoidable. Here, we demonstrate the nonlinear superconducting metamaterial resonators, wherein frequency intervals between the nearest-neighbor modes are unequal, by using the composite right/left-handed transmission lines. The microwave transport properties are analyzed by the developed real-space approach, instead of the usual equivalent circuit method. The devices are fabricated by using the usual electron beam evaporation technique, and their microwave transport parameters are measured at 50 mK temperature. The observations are basically consistent with the relevant theoretical predictions and also numerical simulations. Hopefully, the demonstrated nonlinear devices, with well-isolated modes, could be used to encode the superconducting qubits for microwave quantum information processing.

Colorectal cancer (CRC) is a major global health concern, and the development of effective treatment strategies is crucial. Enzyme prodrug therapy (EPT) shows promise in combating tumors but faces challenges in achieving sustained expression of therapeutic enzymes and optimal biological distribution. To address these issues, a fungi-triggered in situ chemotherapeutics generator (named as SC@CS@5-FC) was constructed via oral delivery of a prodrug (5-fluorocytosine, 5-FC) for the treatment of orthotopic colorectal tumor. When SC@CS@5-FC targets the tumor through tropism by Saccharomyces cerevisiae(SC), the chemotherapeutic generator could be degraded under abundant hyaluronidase (HAase) in the tumor microenvironment by an enzyme-responsive gate to release prodrug (5-FC). And nontoxic 5-FC was catalyzed to toxic chemotherapy drug 5-fluorouracil (5-FU) by cytosine deaminase (CD) of SC. Meanwhile, SC and zinc-coordinated chitosan nanoparticles could be used as immune adjuvants to activate antigen-presenting cells and further enhance the therapeutic effect. Our results demonstrated that SC@CS@5-FC could effectively inhibit tumor growth and prolong mouse survival in an orthotopic colorectal cancer model. This work utilizes living SC as a dynamotor and positioning system for the chemotherapeutic generator SC@CS@5-FC, providing a strategy for oral enzyme prodrug therapy for the treatment of orthotopic colorectal.

Superconductivity involving finite-momentum pairing1can lead to spatial-gap and pair-density modulations, as well as Bogoliubov Fermi states within the superconducting gap. However, the experimental realization of their intertwined relations has been challenging. Here we detect chiral kagome superconductivity modulations with residual Fermi arcs in KV3Sb5and CsV3Sb5using normal and Josephson scanning tunnelling microscopy down to 30 millikelvin with a resolved electronic energy difference at the microelectronvolt level. We observe a U-shaped superconducting gap with flat residual in-gap states. This gap shows chiral 2a × 2aspatial modulations with magnetic-field-tunable chirality, which align with the chiral 2a × 2apair-density modulations observed through Josephson tunnelling. These findings demonstrate a chiral pair density wave (PDW) that breaks time-reversal symmetry. Quasiparticle interference imaging of the in-gap zero-energy states reveals segmented arcs, with high-temperature data linking them to parts of the reconstructed vanadium d-orbital states within the charge order. The detected residual Fermi arcs can be explained by the partial suppression of these d-orbital states through an interorbital 2a × 2aPDW and thus serve as candidate Bogoliubov Fermi states. In addition, we differentiate the observed PDW order from impurity-induced gap modulations. Our observations not only uncover a chiral PDW order with orbital selectivity but also show the fundamental space–momentum correspondence inherent in finite-momentum-paired superconductivity.

Charge density waves appear in numerous condensed matter platforms ranging from high-temperature superconductors to quantum Hall systems. Despite such ubiquity, there has been a lack of direct experimental study of boundary states that can uniquely stem from the charge order. Here we directly visualize the bulk and boundary phenomenology of the charge density wave in a topological material, Ta2Se8I, using scanning tunnelling microscopy. At a monolayer step edge, we demonstrate the presence of an in-gap boundary mode persisting up to the charge ordering temperature with modulations along the edge that match the charge density wave wavevector along the edge. Furthermore, these results manifesting the presence of an edge state challenge the existing axion insulator interpretation of the charge-ordered phase in this compound.

Refill friction stir spot welding (RFSSW) provides a novel method to join similar and/or dissimilar metallic materials without a key-hole in the center of the joint. Having the key-hole free characterization, the similar/dissimilar RFSSW joint exhibits remarkable and endurable characteristics, including high shear strength, long fatigue life, and strong corrosion resistance. In the meanwhile, as the key-hole free joint has different microstructures compared with conventional friction stir spot welding, thus the RFSSW joint shall possess different shear and fatigue fracture mechanisms, which needs further investigation. To explore the underlying failure mechanism, the similar/dissimilar metallic material joining parameters and pre-treatment, mechanical properties, as well as fracture mechanisms under this novel technology will be discussed. In details, the welding tool design, welding parameters setting, and the influence of processing on the lap shear and fatigue properties, as well as the corrosion resistance will be mainly discussed. Moreover, the roadmap of RFFSW is also discussed.

Photonic reservoir computing (RC) is a kind of artificial neural network (ANN) structure which is easy to train, with higher accuracy and speed, and has important application prospects in various fields, such as the time-series prediction, waveform recognition, speech recognition, nonlinear channel equalization, etc. In this work, we demonstrated a comprehensive numerical investigation on the characteristics and physical mechanisms of dual-channel and parallel RC based on vertical-cavity surface-emitting laser (VCSEL-RC) with filtered optical feedback (FOF). Using the dual-channel time-series prediction tasks as standard benchmark, the effects of feedback parameters (feedback strength, filter bandwidth, feedback detuning) and type on normalized mean square error (NMSE) were explored in detail. We found that: Selecting a smaller filter bandwidth can widen the range of values of feedback strength corresponding to smaller NMSE, which can effectively strengthen the robustness of parallel VCSEL-RC; When the feedback detuning varies from positive to negative value, the range of parameters space for feedback strength-filter bandwidth corresponding to lower NMSE tends to be narrowed; Compared with parallelly polarized FOF (PP-FOF), orthogonally polarized FOF (OP-POF) shows a stronger robustness enhancement; For smaller feedback strength, NMSE value is insensitive to the interior parameters of VCSEL. We also evaluated the processing rate of parallel VCSEL-RC with FOF. This study is valuable on enriching the understanding for nonlinear dynamics of FOF-based VCSEL-RC, and can provide a design guideline towards parallel, dual-channel RC with robust performance.

Overtaking is a common driving behaviour used by human drivers while driving. Therefore, the decision on overtaking is very important in the automatic driving decision. To be able to improve the passing efficiency of intelligent vehicles, it is crucial to be able to interact with oncoming vehicles with different driving styles. An overtaking decision needs to be adapted to the situation where the vehicle being overtaken is potentially stationary or moving. Therefore, this paper proposes an overtaking decision method based on potential conflict area based on the requirements. Firstly, the planning method for each stage is given, and the generation method of the potential conflict area is proposed. Second, the interaction process between the host vehicle and the opposite oncoming vehicle is modelled by a dynamic game based on the potential conflict area. A driving style assessment method for oncoming vehicles based on potential conflict area is proposed. Thirdly, the priority of passing the potential conflict area of multiple oncoming vehicles is divided to correct the speed planning in the waiting and the speed payoff function in the game. Finally, the overtaking decision is simulated and validated by Virtual Test Drive.

The origin of agriculture in the farming-pastoral zone of northern China remains in dispute. The central region of the Inner Mongolia Plateau is located in the core area of the farming-pastoral zone; thus, it is a critical region for exploring the origin of the dryland farming system in northern China. This study selected the Yumin Site and Banan Site, which belong to the Yumin Culture-the beginning of Neolithic culture in Inner Mongolia-as the research objects. Based on the quartz optically stimulated luminescence (OSL) dating on the sedimentary sections from the Yumin site (YM) and Banan site (BN1 and BN2), the Holocene chronology framework of each section was established. After that, by identifying carbonized grains in the Yumin site and the multi-proxy analysis of each section, we investigated the relationship between the origin of agriculture and climate change in this region. The results revealed that the timing of the origin of agriculture recorded in the Yumin site lagged behind the timing of a significant increase of precipitation during the early Holocene but coincided with the timing of a significant increase of vegetation around 8.4 ka. This phenomenon was further confirmed by the published high-resolution paleoenvironmental records from the surrounding area of the Yumin Culture. We propose that with the gradual amelioration of hydrothermal conditions since the beginning of the Holocene, the regional ecosystem had been improved, resulting in the gradual conversion of the land surface from infertile sand to organic-rich soil, providing an appropriate environmental foundation for the origin of dryland farming in northern China around 8.4 ka. This study highlighted that the “accumulative environmental effects” during the early Holocene played a vital role in the origin of agriculture in northern China and provided a reference for agricultural management in the context of future climate change.

Microreactors are highly efficient devices with a large specific surface area to improve the mass transfer efficiency. In this paper, a comprehensive three-dimensional CFD model was constructed based on three mass transfer theories to simulate the liquid-liquid two-phase flow and mass transfer process in a microchannel reactor, and two enhancement schemes were proposed. The multiphase flow and mass transfer characteristics were investigated by visualization and extraction experiments. The results indicated that the extraction efficiencies (E) and overall mass transfer coefficients (KLa) calculated by the penetration model and surface renewal model were within ±15 % errors compared to the experimental values. Moreover, Eprimarily increases with the increase of fluid residence time, while KLaincreases with increasing flow rate. As the flow rate increases from 0.3 ml/min to 1.5 ml/min, Edecreases by 15 %, and KLarises from 0.78 s⁻¹ to 2.65 s⁻¹. Whereas the channel width decreases from 0.8 mm to 0.3 mm, Edecreases by 3 %, and KLarises from 0.44 s⁻¹ to 2.77 s⁻¹. Finally, microchannel with necked structure and baffles in mixing zone both improve the mass transfer efficient to some extent.

Reported herein is a practical, economical, and efficient construction of 3-alkylated quinoxalin-2(1H)-ones with alkyl carboxylic acids and alkyl iodides by quinoxalin-2(1H)-one excitation and cobaloxime catalysis. Primary, secondary, and tertiary alkyl iodides and carboxylic acids all could be efficiently transferred into target products with excellent functional group tolerance. Mechanism studies reveal that the quinoxalin-2(1H)-one derivatives could be directly excited and yield alkyl carbon radicals from alkyl carboxylic acids and alkyl iodides with the aid of the cobaloxime complex.

Di-2-ethylhexyl phthalate (DEHP) is frequently used as a plasticizer to enhance the plasticity and durability of agricultural products, which pose adverse effects to human health and the environment. Aquaporin 1 (AQP1) is a main water transport channel protein and is involved in the maintenance of intestinal integrity. However, the impact of DEHP exposure on gut health and its potential mechanisms remain elusive. Here, we determined that DEHP exposure induced a compromised duodenum structure, which was concomitant with mitochondrial structural injury of epithelial cells. Importantly, DEHP exposure caused duodenum inflammatory epithelial cell damage and strong inflammatory response accompanied by activating the TLR4/MyD88/NF-κB signaling pathway. Mechanistically, DEHP exposure directly inhibits the expression of AQP1 and thus leads to an inflammatory response, ultimately disrupting duodenum integrity and barrier function. Collectively, our findings uncover the role of AQP1 in phthalate-induced intestinal disorders, and AQP1 could be a promising therapeutic approach for treating patients with intestinal disorders or inflammatory diseases.

Copper, permalloy, cobalt, and silicon are the materials that have been widely utilised in magnetic devices. When the size of interest is down to the nanoscale, the inter-diffusion between certain materials becomes influential. This paper studies the nanoscale friction characteristics between frictional pairs with and without inter-diffusion properties through the atomic force microscope. The distinct evolution features of nanoscale friction force when inter-diffusion is involved are discovered experimentally, which is also confirmed through theoretical analysis. Firstly, through the thin film deposition method, four pairs of contact materials (Cu–Ni81Fe19, Si–Ni81Fe19, Cu–Co, Cu–Si) are designed for friction tests, in which diffusion occurs at the interface of Cu–Ni81Fe19pair. Then, the effects of sliding velocity and loading force on the nano friction of each pair are measured. It is found that regardless of the diffusion phenomenon: (1) the adhesion force values exhibit a notable correlation to the values of the friction force; (2) the friction force in all four material pairs consistently increases with the growth of the normal loading force, although the growth rate may differ. In terms of the sliding velocity effect, the friction forces of immiscible materials (Si–Ni81Fe19, Cu–Co, and Cu–Si) are found to increase with the increasing sliding velocity. However, the friction force of Cu–Ni81Fe19, decreases with the increasing sliding velocity. Furthermore, a compositive friction model considering both the velocity and the normal force effect was proposed, which shows good agreement with the experimental results and explains the nano friction behaviour of both miscible and immiscible metals.

Artificial photoelectrochemistry (PEC) has emerged as a promising and efficient technology for the sustainable conversion of solar energy into chemicals. In this study, we present a refined PEC process that enables the highly selective and stable production of piperonal and other valuable aldehydes through the oxidation of the corresponding alcohols. By employing Fe2O3or TiO2as the photoanode material and 2,2,6,6-tetramethylpiperidinooxy (TEMPO) as a redox mediator in an H2O/acetonitrile solution, we achieve 100% selectivity and a >95% Faradaic efficiency for piperonal production from piperonyl alcohol (PA) oxidation. Remarkably, we reveal the enhancing effect on the PA oxidation reactivity of appropriate-amount water in the solvent as it plays a crucial role in inhibiting the photoelectron–hole recombination efficiency and facilitating charge transfer. Mechanistic analysis suggests that TEMPO-mediated PA oxidation involves the formation of •O2–radicals by the reduction of oxygen on the cathode, resulting in water as the sole byproduct. Furthermore, our PEC oxidation system exhibits applications on the 100%-selective production of various conjugated aldehydes, including 4-anisaldehyde, cuminaldehyde, and the vitamin B6 derivative. By implementing a TiO2//Fe2O3dual-photoanode system, we achieve an enhanced piperonal production rate of 31.2 μmol h–1cm–2at 1.0 V vs Ag/Ag+and demonstrate its stability over a 102 h cyclic test, ensuring near-quantitative yield. This research illuminates the potential of the PEC strategy as a generally applicable method for the efficient production of high-value aldehydes.

Over the past five decades, heavy reliance on pesticides in global food production has raised concerns regarding the efficiency of pest control and environmental contamination. Consequently, the development of supramolecular drug carriers based on host–guest interactions, particularly cyclodextrins, has shown promise in precision agriculture due to their predictable and adjustable properties. In this study, a series of amphiphilic random copolymers incorporating hydrophilic acrylamide and hydrophobic benzotriazole were designed and synthesized through coprecipitation to form a supramolecular inclusion complex. The copolymer and inclusion complex demonstrated pH-responsive behavior, which enabled the controlled release of benzotriazole for the targeted control of B. cinerea, a destructive phytopathogen that causes gray mold disease. The antimicrobial activity of the complex was observed to be superior in targeting specific SF9 cells compared to HepG2 cells and exhibited favorable biosafety. The biological activity and cytotoxicity of these products were evaluated, demonstrating their potential for protecting plants and fruits against B. cinerea.

Investigating novel nonlinear optical (NLO) active units serves as a valuable method for broadening the research landscape of NLO materials. This study showcases the potential of the cytosinium cation (C4H6N3O)+as a novel NLO-active motif through theoretical calculations. The title compound exhibited a wide band gap of 3.85 eV, along with a moderate second harmonic generation (SHG) response of 1.65 times that of KH2PO4(KDP) and significant birefringence of 0.47. Its exceptional optical properties are primarily attributed to the synergy interaction between cations and anionic groups in the asymmetric unit.

•Thermochemical conversion reactions of biomass are of great complexity and diversity.•Thermal analysis techniques vary with the sample loading and heating methods.•Each analysis reactor has its advantages and limitations for thermal analysis.•Gas flow condition, transport effect, heating rate, and temperature distribution are the most critical issues.•Thermal analysis techniques need to be continuously developed.

Oxide dispersion strengthened (ODS) steel is one of the most promising materials for nuclear applications. However, there are fewer studies on the spot welding of ODS steel, and the softening mechanism of ODS steel resistance spot welded joint is unclear. The microstructural features of the ODS resistance spot welded joint was characterized to analyze the softening mechanism. The failure behavior and tensile shear performance were studied combined with finite element simulation. The results showed that the fusion boundary has the lowest hardness and the softening zone is divided into fusion zone(FZ) softening and heat affected zone(HAZ) softening according to different location in the joint. In FZ softening, the softening is mainly caused by the presence of δ-ferrite and fewer oxides as well as lower dislocation density. In HAZ softening, the softening is mainly caused by larger grains, less oxides. There are two types of failure, the fracture initiated at HAZ softening shows a brittle feature, while initiated at FZ softening shows a ductile feature. The softening leads to a reduction in tensile-shear strength. Thus, the control of softening zone is critical to improve the reliability of welded joints.

P3-layered transition oxide cathodes have garnered considerable attention owing to their high initial capacity, rapid Na+kinetics, and less energy consumption during the synthesis process. Despite these merits, their practical application is hindered by the substantial capacity degradation resulting from unfavorable structural transformations, Mn dissolution and migration. In this study, we systematically investigated the failure mechanisms of P3 cathodes, encompassing Mn dissolution, migration, and the irreversible P3–O3′ phase transition, culminating in severe structural collapse. To address these challenges, we proposed an interfacial spinel local interlocking strategy utilizing P3/spinel intergrowth oxide as a proof-of-concept material. As a result, P3/spinel intergrowth oxide cathodes demonstrated enhanced cycling performance. The effectiveness of suppressing Mn migration and maintaining local structure of interfacial spinel local interlocking strategy was validated through depth-etching X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, and in situ synchrotron-based X-ray diffraction. This interfacial spinel local interlocking engineering strategy presents a promising avenue for the development of advanced cathode materials for sodium-ion batteries.

Coarse austenite grains are unavoidable in the low carbon steels processed by twin-roll strip casting. Unfortunately, the polygonal ferrite (PF) grains cannot be refined by conventional on-line cooling process, resulting in low strength. In this work, an on-line heat treatment including reaustenitizing and subsequent controlled cooling was performed in laboratory to form heterogeneous microstructures composed of PF and acicular ferrite (AF). It has been founded that increased prior austenite grain size and the cooling rate led to more AF laths, which inhibited the growth of PF grains. When the prior austenite grain size is less than 60 μm, the formation of AF is suppressed. The tensile tests indicate that the heterostructured steels exhibited higher yield strength than the samples without AF. The improvement of yield strength can be attributed to the grain boundary strengthening, dislocation strengthening and back stress strengthening. The higher AF volume fraction leads to higher dislocation density in PF grains, and more AF/PF interfaces may increase the amount of accumulated geometrically necessary dislocations. Therefore, the contributions of dislocation and back stress strengthening increase with the increase of AF volume fractions. High dislocation density and the generation of back stress contribute a high strain hardening rate to delay the necking and sustain good plasticity. Moreover, the heterostructured steels exhibit the two-stage work hardening behavior during tensile test, which indicates that plastic deformation starts in PF grains while the AF laths remain in elastic state, and then plastic deformation occurs in both strain hardened PF grains and AF laths.

Topology1–3and interactions are foundational concepts in the modern understanding of quantum matter. Their nexus yields three important research directions: (1) the competition between distinct interactions, as in several intertwined phases, (2) the interplay between interactions and topology that drives the phenomena in twisted layered materials and topological magnets, and (3) the coalescence of several topological orders to generate distinct novel phases. The first two examples have grown into major areas of research, although the last example remains mostly unexplored, mainly because of the lack of a material platform for experimental studies. Here, using tunnelling microscopy, photoemission spectroscopy and a theoretical analysis, we unveil a ‘hybrid’ topological phase of matter in the simple elemental-solid arsenic. Through a unique bulk-surface-edge correspondence, we uncover that arsenic features a conjoined strong and higher-order topology that stabilizes a hybrid topological phase. Although momentum-space spectroscopy measurements show signs of topological surface states, real-space microscopy measurements unravel a unique geometry of topologically induced step-edge conduction channels revealed on various natural nanostructures on the surface. Using theoretical models, we show that the existence of gapless step-edge states in arsenic relies on the simultaneous presence of both a non-trivial strong Z2invariant and a non-trivial higher-order topological invariant, which provide experimental evidence for hybrid topology. Our study highlights pathways for exploring the interplay of different band topologies and harnessing the associated topological conduction channels in engineered quantum or nano-devices.

Atomically dispersed dual-site catalysts can regulate multiple reaction processes and provide synergistic functions based on diverse molecules and their interfaces. However, how to synthesize and stabilize dual-site single-atom catalysts (DACs) is confronted with challenges. Herein, we report a facile high-temperature gas-migration strategy to synthesize Fe–Ni DACs on nitrogen-doped carbon nanosheets (FeNiSAs/NC). FeNiSAs/NC exhibits a high half-wave potential (0.88 V) for the oxygen reduction reaction (ORR) and a low overpotential of 410 mV at 10 mA cm–2for the oxygen evolution reaction (OER). As an air electrode for Zn–air batteries (ZABs), it shows better performances in aqueous ZABs and excellent stability and flexibility in solid-state ZABs. The high specific surface area (1687.32 m2/g) of FeNiSAs/NC is conducive to electron transport. Density functional theory (DFT) reveals that the Fe sites are the active center, and Ni sites can significantly optimize the free energy of the oxygen-containing intermediate state on Fe sites, contributing to the improvement of ORR and the corresponding OER activities. This work can provide guidance for the rational design of DACs and understand the structure–activity relationship of SACs with multiple active sites for electrocatalytic energy conversion.

A profound understanding of the band-edge electronic structure is crucial for advancing the development of highly efficient photocatalytic materials and unraveling the underlying mechanisms. This study employs a unified and consistent assessment protocol, offering a systematic exploration of the inherent connections between the band-edge electronic structure and the photo(electro)catalytic performance of a series of delafossite ABO2compounds (A = Cu, Ag; B = Al, Ga, In). These compounds exhibit characteristics of indirect bandgap semiconductors, with fundamental and optical bandgaps spanning from 1.45 to 3.57 eV. Notably, the Cu-based ABO2compounds display a significantly larger fundamental bandgap and excel as photocathode materials when the B-site element is held constant. Among these, CuInO2emerges as the most promising candidate, showcasing superior photo(electro)catalytic performance. Extensive density functional theory calculations unravel intricate insights into the interplay between the band-edge electronic structure and valence orbital hybridization of the A- and B-site elements, providing invaluable perspectives for comprehending and enhancing the photo(electro)catalytic performance of such compounds. The findings in this study not only establish robust theoretical foundations for integrating ABO2compounds into the field of photo(electro)catalysis but also lay the groundwork for future material design and optimization.

The presence of particles and the shock waves generated by the cavitation bubbles can significantly affect the safety and the performance of hydrodynamic machineries. In the present paper, the shock waves generated by cavitation bubble collapsing near the particle are numerically investigated based on the OpenFOAM together with the numerical schlieren for the shock wave identifications. The numerical results reveal that the stand-off distance is one of the paramount factors affecting the interactions between the particle and the shock waves. Several different kinds of shock waves (e.g., bubble-inception, jet formation, particle reflected and jet-split shock waves) are observed during the bubble collapsing near the particle. For stand-off distance smaller than 0.5 or larger than 1.1, the maximum pressure at particle surface generated by the bubble growth can surpass those of the collapse stage.

Rolling bearings working in oscillating applications often suffer from false brinelling and fretting corrosion that limit their service life. At present, the study of oscillation-induced failures is primarily dominated by a large number of sliding and bench tests. However, most of the previous work are not able to fully describe the two closely related but different failure mechanisms. In this study, the origin and evolution of the two failures are thoroughly investigated under strictly controlled oscillating rolling conditions. The results show that failure evolves from false brinelling to fretting corrosion under dry friction conditions regardless of the oscillation amplitude. This process is accompanied by a large area peeling and serious oxidation, and the oxygen content increases from 2.50 wt% to 21.22 wt%. Oxidation is a crucial factor in the evolution of false brinelling into fretting corrosion. However, the distribution of microwear and oxygen content depend on the oscillation amplitude. Under lubrication conditions, the friction coefficient (COF) is smaller in the initial stage and led to local slip or transient instability of rolling elements. Therefore, the size of the wear marks and COF increased and appeared to be larger than those under a dry friction condition. However, grease can separate the contact surfaces, only surface deformation owing to false brinelling and slight damage at the roughness level occurred. The evolution of false brinelling and fretting corrosion is also closely related to residual stress. False brinelling often occurrs with residual stress accomulation, meanwhile, the residual stress increases from 120 to 300 MPa. When peeling occurs, residual stress is released. The failure pattern transformed from false brinelling to fretting corrosion and is accompanied by oxidation. So far, none of investigation is able to show satisfactory evolution of oscillating-induced failures, this study may contribute to more scientific understanding of rolling bearings against long-run reciprocating oscillating wear.

Di-(2-ethylhexyl) phthalate (DEHP), as the most common phthalate, has been extensively used as a plasticizer to improve the plasticity of agricultural products, which pose severe harm to human health. Mitochondrial dynamics and endoplasmic reticulum (ER) homeostasis are indispensable for maintaining mitochondria-associated ER membrane (MAM) integrity. In this study, we aimed to explore the effect of DEHP on the nervous system and its association with the ER–mitochondria interaction. Here, we showed that DEHP caused morphological changes, motor deficits, cognitive impairments, and blood–brain barrier disruption in the brain. DEHP triggered ER stress, which is mainly mediated by protein kinase R-like endoplasmic reticulum kinase (PERK) signaling. Moreover, DEHP-induced mitofusin-2 (Mfn2) downregulation results in imbalance of the mitochondrial dynamics. Interestingly, DEHP exposure impaired MAMs by inhibiting the Mfn2-PERK interaction. Above all, this study elucidates the disruption of the Mfn2-PERK axis-mediated ER–mitochondria interaction as a phthalate-induced neurotoxicity that could be potentially developed as a novel therapy for neurological diseases.

Our objective was to investigate the status and influence of myopia among primary school students in Fushun, Liaoning Province, China. We aimed to provide a theoretical and epistemological basis for implementing myopia prevention initiatives. We employed cluster sampling and surveyed 5216 primary school students from grades 1–6 across eight primary schools in Fushun City. Our participants included 2606 males and 2610 females whose average age was 9.25 (SD= 1.76) years. The rate of myopia among these primary school students was 29.54%, with statistically significant differences among students of different genders and grades. Logistic regression analysis further identified several possible protective factors, including appropriate reading distance, adequate home lighting, regular breaks between classes, conscientious eye exercises, and daily outdoor physical activity. Conversely, the associated risk factors were being female, being in a higher grade level, spending more than 4 hours on homework, occasionally reading while lying down, and having one or both parents with myopia. Overall, our results indicated a high incidence of myopia, highlighting the need for scientifically controlled interventions to manage and mitigate the occurrence and progression of myopia in this population.

The selective modification of carbohydrates is significant for producing their unnatural analogues for drug discovery. C1-functionalization (glycosylation) and C1,C2-difunctionalization of carbohydrates have been well developed. In contrast, C3-functionalization or C1,C3-difunctionalization of carbohydrates remains rare. Herein, we report such processes that efficiently and stereoselectively modify carbohydrates. Specifically, we found that trifluoroethanol (TFE) could promote 1,3-bis-indolylation/pyrrolylation of 2-nitroglycals generated carbohydrate derivatives in up to 93% yield at room temperature; slightly reducing the temperature could install two different indoles at the C1- and C3-positions. Switching TFE to a bifunctional amino thiourea catalyst leads to the generation of C3 monosubstituted carbohydrates, which could also be used to construct 1,3-di-C-functionalized carbohydrates. This approach produced a range of challenging sugar derivatives (over 80 examples) with controllable and high stereoselectivity (single isomer for over 90% of the examples). The potential applications of the reaction were demonstrated by a set of transformations including the synthesis of bridged large-ring molecules and gram scale reactions. Biological activities evaluation demonstrated that three compounds exhibit a potent inhibitory effect on human cancer cells T24, HCT116, AGS, and MKN-45 with IC50ranged from 0.695 to 3.548 μM.

We herein report an unprecedented organic–inorganic hybrid borate incorporating a novel nonlinear-optical (NLO) active unit, namely, [C(NH2)3][B(C2O2H4)2]. The novel NLO active unit was derived from the condensation reaction between two glycol molecules and one (BO4)5–group. The title compound exhibits a moderate second-harmonic-generation effect (0.7 × KDP), a significant band gap (5.76 eV), and a suitable birefringence (0.078 at 550 nm). The optical properties are determined by the synergistic interaction between the C(NH2)3+cation and the [B(C2O2H4)2]-group, as indicated by theoretical calculations.

The welding arc, as a carrier for the conversion of electrical energy to thermal energy, has a direct impact on the quality of welding by its properties and states. In the tungsten inert gas (TIG) welding process under the condition of Ar–He alternating gas supply, the arc is alternately converted between Ar arc and He arc with an alternating gas supply cycle, which has obvious arc change characteristics. The FLUENT software was used to numerically simulate the characteristics of the TIG arc under the condition of alternating gas supply, and the arc temperature field, arc pressure, electric potential and current density distribution under the condition of alternating gas supply were obtained. Combined with the real-time data of arc pressure measured by the water-cooled copper plate with holes, it is proved that the TIG arc has obvious dynamic characteristics under the condition of Ar–He alternating gas supply. This unique dynamic TIG arc acts on the 5A06 aluminum alloy weld, causing the molten pool to stir, resulting in uniform microstructure and grain refinement at the weld, and thereby improving the mechanical properties of the welded joint.

Changes in hydrological processes and water resources required to sustain vegetation for ecological restoration of landfill covers and post mining sites in arid environments pose challenges in the context of extended droughts. Knowledge of actual threshold and wilting suction values based on tree morphological feature or plant age is essential for understanding the variation of root water uptake with drought stress and numerically predict the pore water pressure profile in root zone. The objective of this study is to quantify the transpiration reduction function (TRF; in terms of stomatal conductance (SC) and xylem sap flow (SF)) of Schefflera arboricola,considering the effects of tree morphology. Continuous drought condition was applied on the plant quantified with leaf area index (LAI) values at 0.5, 2 and 3.5, wherein each LAI represent tree age. The soil matric suction (ψ) and volumetric water content were measured by embedded sensors in the root zone. Based on the TRF obtained from SC values, a unique threshold suction (ψNTRt) ranging from 30 to 50 kPa was identified. Beyond this ψNTRt, measured leaf abscisic acid concentration increased up to 35 ng/mL, indicating the start of water stress avoidance mechanism. It is evident that ψNTRtis independent of tree morphological parameter- leaf area to root length ratio (LA/RL). On the contrary, a threshold suction (ψSAPt), depending on LA/RL ratio, can be determined, indicating the start of xylem cavitation. This ψSAPtvalues ranging from 80 to 500 kPa depending on the LA/RL value, imply that the plant could significantly resist xylem embolization at higher LA/RL. In contrast, the plant with low LA/RL values have less tolerance of drought stress and hence low survivability. The results from this research study can be vital for devising and predicting plant available water in water scarce arid environments by a flux-based approach which is dependent on the tree age.

All-solid-state potassium metal batteries have been considered promising candidates for large-scale energy storage because of abundance and wide availability of K resources, elimination of flammable liquid organic electrolytes, and incorporation of high-capacity K metal anode. However, unideal K-ion conductivities of most reported K-ion solid electrolytes have restricted the development of these batteries. Herein, a novel K2B10H10·CO(NH2)2complex is reported, forming by incorporating urea into K2B10H10, to achieve an enhanced K-ion conductivity. The crystal structure of K2B10H10·CO(NH2)2was determined as a monoclinic lattice with the space group of C2/c(No. 15). K2B10H10·CO(NH2)2delivers an ionic conductivity of 2.7 × 10–8S cm–1at 25 °C, and reaching 1.3 × 10–4S cm–1at 80 °C, which is about 4 orders of magnitude higher than that of K2B10H10. One possible reason is the anion expansion in size due to the presence of dihydrogen bonds in K2B10H10·CO(NH2)2, resulting in an increase in the K–H bond distance and the electrostatic potential, thereby enhancing the mobility of K+. The K-ion conductivity is also higher than those of most hydridoborate-based K-ion conductors reported. Besides, K2B10H10·CO(NH2)2reveals a wide electrochemical stability window and remarkable interface compatibility with K metal electrodes, suggesting a promising electrolyte for all-solid-state K metal batteries.

Lead halide perovskite nanocrystals with excellent photophysical properties are promising electrochemiluminescence (ECL) candidates, but their poor stability greatly restricts ECL applications. Herein, hydrogen-bonded cocrystal-encapsulated CsPbBr3perovskite nanocrystals (PeNCs@NHS-M) were synthesized by using PeNCs as nuclei for inducing the crystallization of melamine (M) and N-hydroxysuccinimide (NHS). The as-synthesized composite exhibits multiplicative ECL efficiencies (up to 24-fold that of PeNCs) without exogenous coreactants and with excellent stability in the aqueous phase. The enhanced stability can be attributed to the well-designed heterostructure of the PeNCs@NHS-M composite, which benefits from both moiety passivation and protection of the peripheral cocrystal matrix. Moreover, the heterostructure with covalent linkage facilitates charge transfer between PeNCs and NHS-M cocrystals, realizing effective ECL emission. Meanwhile, the NHS and M components act as coreactants for PeNCs, shortening the electron-transport distance and resulting in a significant increase in the ECL signal. Furthermore, by taking advantage of the specific binding effect between NHS-M and uranyl (UO22+), an ECL system with both a low detection limit (1 nM) and high selectivity for monitoring UO22+in mining wastewater is established. The presence of UO22+disrupted the charge-transfer effect within PeNCs@NHS-M, weakening the ECL signals. This work provides an efficient design strategy for obtaining stable and efficient ECLs from perovskite nanocrystals, offering a new perspective for the discovery and application of perovskite-based ECL systems.

The key to searching novel nonlinear optical (NLO) crystals was effectively combining the NLO-active units to obtain a noncentrosymmetric structure. Nevertheless, the present predicament lies in the growing challenge of discovering novel crystals within conventional inorganic frameworks that surpass the properties of the current NLO materials. In view of this, researchers expanded their research focus to the organic–inorganic hybridization system; it is foreseeable to concentrate the advantages from several kinds of NLO-active units to acquire novel NLO crystals with superior properties. We herein report an organic–inorganic hybrid molybdate crystal, namely, [C(NH2)3]6Mo7O24(GMO). It was successfully obtained via combining inorganic NLO-active MoO6octahedra and organic π-conjugated [C(NH2)3]+groups. GMO demonstrates a moderate second-harmonic-generation response, specifically measuring about 1.3 times the value of KDP. Additionally, it exhibits a significant birefringence value of 0.203 at the wavelength of 550 nm and possesses a wide band gap of 3.31 eV. Theoretical calculations suggest that the optical properties of the GMO are primarily influenced by the synergy effect of [C(NH2)3]+groups between MoO6octahedra.

Six new sesquiterpene quinone/hydroquinone meroterpenoids, arenarialins A–F (1–6), were isolated from the marine sponge Dysidea arenariacollected from the South China Sea. Their chemical structures and absolute configurations were determined by HRMS and NMR data analyses coupled with DP4+ and ECD calculations. Arenarialin A (1) features an unprecedented tetracyclic 6/6/5/6 carbon skeleton, whereas arenarialins B–D (2–4) possess two rare secomeroterpene scaffolds. Arenarialins A–F showed inhibitory activity on the production of inflammatory cytokines TNF-α and IL-6 in LPS-induced RAW264.7 macrophages with arenarialin D regulating the NF-κB/MAPK signaling pathway.

The thermal safety of lithium batteries is greatly improved by regulations of internal thermal-responsive components including electrolytes, separators, and cathode materials.

It remains a tremendous challenge to achieve high-efficiency bifunctional electrocatalysts for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) for hydrogen production by water splitting. Herein, a novel hybrid of 0D nickel nanoparticles dispersed on the one-dimensional (1D) molybdenum carbide micropillars embedded in the carbon layers (Ni/Mo2C@C) was successfully prepared on nickel foam by a facile pyrolysis strategy. During the synthesis process, the nickel nanoparticles and molybdenum carbide were simultaneously generated under H2and C2H2mixed atmospheres and conformally encapsulated in the carbon layers. Benefiting from the distinctive 0D/1D heterostructure and the synergistic effect of the biphasic Mo2C and Ni together with the protective effect of the carbon layer, the reduced activation energy barriers and fast catalytic reaction kinetics can be achieved, resulting in a small overpotential of 96 mV for the HER and 266 mV for the OER at the current density of 10 mA cm–2together with excellent durability in 1.0 M KOH electrolyte. In addition, using the developed Ni/Mo2C@C as both the cathode and anode, the constructed electrolyzer exhibits a small voltage of 1.55 V for the overall water splitting. The novel designed Ni/Mo2C@C may give inspiration for the development of efficient bifunctional catalysts with low-cost transition metal elements for water splitting.

Currently, a lot of work is focused on aerial object detection and has achieved good results. Though these methods have achieved promising results on the conventional datasets, it is still challenging to locate objects from the low-quality images captured in adverse weather conditions. Currently, there are limited approaches that combine aerial object detection with hazy conditions, and there are few publicly available datasets for real hazy weather based on aerial images. For this purpose, we propose a dataset HRSI, hazy remote sensing images in the real world, which is mainly divided into three categories: airport, large vehicle, and ship. All images in HRSI are from real hazy conditions. In addition, we propose an object detection model DFENet, a dehazing feature enhancement model for hazy remote sensing images, which is suitable for hazy weather. DFENet consists of a two-branch and a dehazing module. The two-branch structure helps to fully learn hazy and dehazing features. In order to avoid the impact of noise caused by the dehezing module, we also designed a haze-predict module (HPM) to predict the information containing haze in the image. We introduce the cross-fuse module (CFM) to utilize the information of haze to guide the feature fusion of two branches. By utilizing the information of haze, DFENet can dynamically adjust the feature weight in the two-branch to avoid the impact of noise generated by the dehazing module. Compared with traditional object detection methods, DFENet not only has good performance in hazy conditions but also improves performance in clear conditions. We tested DFENet on DOTA, HRSI, and Foggy-DOTA to demonstrate that DFENet performs better under hazy conditions.

Abdominal aortic aneurysm (AAA) is a degenerative disease that caused mortality in people aged >65. Senescence plays a critical role in AAA pathogenesis. Advances in AAA repair techniques have occurred, but a remaining priority is therapies to limit AAA growth and rupture. Our Previous study found cyclic nucleotide phosphodiesterase 1C (PDE1C) exacerbate AAA through aggravate vascular smooth muscle cells (VSMCs) senescence by downregulating Sirtuin1 (SIRT1) expression and activity. Vinpocetine as a selective inhibitor of PDE1 and a clinical medication for cerebral vasodilation, it is unclear whether vinpocetine can rely on SIRT1 to alleviate AAA. This study showed that pre-treatment with vinpocetine remarkably prevented aneurysmal dilation and reduced aortic rupture in elastase-induced AAA mice. In addition, the elastin degradation, MMP (matrix metalloproteinase) activity, macrophage infiltration, ROS production, collagen fibers remodeling, and VSMCs senescence were decreased in AAA treated with vinpocetine. While these effects were unable to exert in VSMCs-specific SIRT1 knockout AAA mice. Accordingly, we revealed that vinpocetine suppressed migration, proliferation, and senescence in VSMCs. Moreover, vinpocetine reduced SIRT1 degradation by inhibiting lysosome-mediated autophagy. In conclusion, this study indicated that vinpocetine may be as a potential drug for therapy AAA through alleviate VSMCs senescence via the SIRT1-dependent pathway.

Microstrain and the associated surface-to-bulk propagation of structural defects are known to be major roadblocks to developing high-energy and long-life batteries. However, the origin and effects of microstrain during the synthesis of battery materials remain largely unknown. Here we perform microstrain screening during real-time and realistic synthesis of sodium layered oxide cathodes. Evidence gathered from multiscale in situ synchrotron X-ray diffraction and microscopy characterization collectively reveals that the spatial distribution of transition metals within individual precursor particles strongly governs the nanoscale phase transformation, local charge heterogeneity and accumulation of microstrain during synthesis. This unexpected dominance of transition metals results in a counterintuitive outward propagation of defect nucleation and growth. These insights direct a more rational synthesis route to reduce the microstrain and crystallographic defects within the bulk lattice, leading to significantly improved structural stability. The present work on microstrain screening represents a critical step towards synthesis-by-design of defect-less battery materials.

The study of logistics network of Yangtze River Delta city group can enable us to understand the logistics integration status. There are 25 cities in Yangtze River Delta Urban Agglomerations selected as the study object of this paper. The values of logistics links to those cities are calculated on the basis of the gravity model. Then, social network analysis method is used to analyze the logistics network density, centrality, cohesive subgroup and core–periphery structure. The research finds that the logistics connection between those cities is low; a few nodes have high degree of centrality and most of these nodes have little difference; there exists subgroup in the network, and the link density inside and between those subgroup are weak; the network has the core–periphery structure; both links inside the marginal area and links between the core area and the edge area are weak, so the network has vulnerabilities. Therefore, some measures need to be taken in in order to realize coordinative development of logistics in Silk Road Economic belt, including breaking the administrative constraints, taking the lead on the core nodes and strengthening the interaction between the edge region and the core region.

A nematic phase breaks the point-group symmetry of the crystal lattice and is known to emerge in correlated materials. Here we report the observation of an intra-unit-cell nematic order and associated Fermi surface deformation in the kagome metal ScV6Sn6. Using scanning tunnelling microscopy and scanning tunnelling spectroscopy, we reveal a stripe-like nematic order breaking the crystal rotational symmetry within the kagome lattice itself. Moreover, we identify a set of Van Hove singularities adhering to the kagome-layer electrons, which appear along one direction of the Brillouin zone and are annihilated along other high-symmetry directions, revealing rotational symmetry breaking. Via detailed spectroscopic maps, we further observe an elliptical deformation of the Fermi surface, which provides direct evidence for an electronically mediated nematic order. Our work not only bridges the gap between electronic nematicity and kagome physics but also sheds light on the potential mechanism for realizing symmetry-broken phases in correlated electron systems.

In this study, a common-node DEM-SPH coupling model based on the shared node method is proposed, and a fluid–structure coupling method using the common-node discrete element method-smoothed particle hydrodynamics (DS-SPH) method is developed using LS-DYNA software. The DEM and SPH are established on the same node to create common-node DEM-SPH particles, allowing for fluid–structure interactions. Numerical simulations of various scenarios, including water entry of a rigid sphere, dam-break propagation over wet beds, impact on an ice plate floating on water and ice accumulation on offshore structures, are conducted. The interaction between DS particles and SPH fluid and the crack generation mechanism and expansion characteristics of the ice plate under the interaction of structure and fluid are also studied. The results are compared with available data to verify the proposed coupling method. Notably, the simulation results demonstrated that controlling the cutoff pressure of internal SPH particles could effectively control particle splashing during ice crushing failure.