查看更多>>摘要：Transport channels with ultrahigh K+selectivity over other ions play a crucial role for living beings,but constructing ionic channels with promising K+selectivity and permeability remains a challenge.Here,an asymmetric bilayer membrane based on MXene(Ti3C2Tx)lamellar channels consisting of a recognition layer(RL)on top of an enhancement layer(EL)exhibits an amazing Matthew effect:amplification of the preferred transport of K+,resulting in an excellent K+-separation performance.The K+ion is selected by the 1-aza-18-crown-6 ether-modified RL,owing to preferential affinity energy,and then rapidly trans-ported as a hydrated ion through the EL,based on the confinement effect.Other undesired ions such as Na+are hindered from entering the RL by the preferred K+occupation of the crown ether.The MXene(Ti3C2Tx)-based Matthew membrane presents high K+-permeation rates of 0.1-0.2 mol·m-2·h-1,with a significant K+/Na+selectivity of 5-9.The molecular separation mechanism of the Matthew membrane is investigated deeply to explore the nature of the Matthew amplification effect on K+sieving,where the precise matching of the RL and EL within the membrane governs the fast K+permeation with good selectivity.The asymmetric structure of our Matthew membrane is the key to understanding the biolog-ical function of ion channels for precise and fast ion transport,which will guide us in the creation of arti-ficial ion channels or membranes.
查看更多>>摘要：Marine corrosion and biofouling are challenges that affect marine industrial equipment,and protecting equipment with functional coatings is a simple and effective approach.However,it is extremely difficult to combine anti-corrosion and anti-fouling properties in a single coating.In this work,we combine reduced graphene oxide(rGO)/silver nanoparticles(AgNPs)with a hydrophilic polymer in a bio-based silicone-epoxy resin to create a coating with both anti-fouling and anti-corrosion properties.The excel-lent anti-fouling performance of the coating results from a ternary synergistic mechanism involving foul-ing release,contact inhibition,and a hydration effect,while the outstanding anti-corrosion performance is provided by a ternary synergistic anti-corrosion mechanism that includes a dense interpenetrating net-work(IPN)structure,a barrier effect,and passivation.The results show that the obtained coating pos-sesses superior anti-fouling activity against protein,bacteria,algae,and other marine organisms,as well as excellent anti-corrosion and certain self-healing properties due to its dynamic cross-linked net-work of rGO/AgNPs and the hydrophilic polymer.This work provides an anti-corrosion and anti-fouling integrated coating for marine industrial equipment.
查看更多>>摘要：Thromboembolism in blood vessels poses a serious risk of stroke,heart attack,and even sudden death if not properly managed.Sonothrombolysis combined with ultrasound contrast agents has emerged as a promising approach for the effective treatment of thromboembolism.Recent reports have highlighted the potential of intravascular sonothrombolysis as a safe and effective treatment modality for deep vein thrombosis(DVT).However,its efficiency has not been validated through in vivo testing of retracted clots.This study aimed to develop a miniaturized multidirectional transducer featuring two 4-layer lead zir-conate titanate(PZT-5A)stacks with an aperture size of 1.4 mm × 1.4 mm,enabling both forward-and side-looking treatment.Integrated into a custom two-lumen 10-French(Fr)catheter,the capability of this device for intravascular sonothrombolysis was validated both in vitro and in vivo.With low-dose tissue plasminogen activators and nanodroplets,the rotational multidirectional transducer reduced the retracted clot mass(800 mg)by an average of 52％within 30 min during in vitro testing.The lysis rate was significantly higher by 37％than that in a forward-viewing transducer without rotation.This improvement was particularly noteworthy in the treatment of retracted clots.Notably,a long-retracted clot(＞10 cm)was successfully treated within 40 min in vivo by creating a flow channel with a diameter＞4 mm in a porcine DVT model.In conclusion,these findings strongly suggest the potential of this technique for clinical applications in sonothrombolysis,offering a feasible solution for effectively treating thromboembolism,particularly in challenging cases involving retracted clots.
查看更多>>摘要：Obstacle detection and platoon control for mixed traffic flows,comprising human-driven vehicles(HDVs)and connected and autonomous vehicles(CAVs),face challenges from uncertain disturbances,such as sensor faults,inaccurate driver operations,and mismatched model errors.Furthermore,misleading sensing information or malicious attacks in vehicular wireless networks can jeopardize CAVs'perception and platoon safety.In this paper,we develop a two-dimensional robust control method for a mixed platoon,including a single leading CAV and multiple following HDVs that incorpo-rate robust information sensing and platoon control.To effectively detect and locate unknown obstacles ahead of the leading CAV,we propose a cooperative vehicle-infrastructure sensing scheme and integrate it with an adaptive model predictive control scheme for the leading CAV.This sensing scheme fuses information from multiple nodes while suppressing malicious data from attackers to enhance robustness and attack resilience in a distributed and adaptive manner.Additionally,we propose a distributed car-following control scheme with robustness to guarantee the following HDVs,considering uncertain disturbances.We also provide theoretical proof of the string stability under this control framework.Finally,extensive simulations are conducted to validate our approach.The simulation results demonstrate that our method can effectively filter out misleading sensing information from malicious attackers,significantly reduce the mean-square deviation in obstacle sensing,and approach the theoretical error lower bound.Moreover,the proposed control method successfully achieves obstacle avoidance for the mixed platoon while ensuring stability and robustness in the face of external attacks and uncertain disturbances.
查看更多>>摘要：Facing the challenges of in-situ utilization of lunar regolith resources,applying an external electric field to manipulate lunar particles has become a promising method for space particle control,which mainly depends on the particle charging properties in the applied electric field.Using the surficial lunar regolith samples brought back from the Moon by the Chang'e-5 mission(CE5 LS),this work successively studied their charging properties,particle dynamics,and their collision damages to aerospace materials under the action of an external electric field in high-vacuum conditions.The results indicated that the charging pro-cess and electrostatic projection of lunar regolith particles under high-vacuum conditions were different from those under atmosphere conditions.The particle diameter range of CE5 LS used in the experiment is 27.7-139.0 μm.For electric field strength of3-12 kV·cm-1,the charge obtained by CE5 LS is 4.8 × 10-15-4.7 × 10-13 C and the charge-to-mass ratio is 1.2 × 10-5-6.8 × 10-4 C·kg-1.The CE5 LS is easier to be negatively charged in an external electric field.Furthermore,significant damages were observed on the target impact surfaces,indicating severe influences of lunar regolith particles on aerospace materials.Our work contributes to a more comprehensive understanding of physical mechanisms controlling the lunar regolith shielding and utilization,and will inspire broad efforts to develop the lunar in-situ engi-neering solutions.
查看更多>>摘要：The lower Cambrian Qiongzhusi((€)1q)shale in the Sichuan Basin,formerly considered a source rock,recently achieved high gas production(7.388 × 105 m3·d-1)from well Z201 in the Deyang-Anyue rift trough(DART),marking an exploration breakthrough of the world's oldest industrial shale gas reser-voir.However,the shale gas enrichment mechanism within the DART is not fully understood.This study reviews the formation of the Qiongzhusi shale gas reservoirs within the DART by comparing them with cotemporaneous deposits outside the DART,and several findings are presented.The gas production interval was correlated with the main phase of the Cambrian explosion(lower Cambrian stage 3).In the early Cambrian ecosystem,dominant animals likely accelerated the settling rates of organic matter(OM)in the upper 1st member of (€)1q((€)1q12)by feeding on small planktonic organisms and producing larger organic fragments and fecal pellets.High primary productivity and euxinic con-ditions contributed to OM enrichment in the lower 1st member of (€)1q(€1q11).Additionally,shale reservoirs inside the DART demonstrated better properties than those outside in terms of thickness,brittle minerals,gas content,and porosity.In particular,the abundant OM pores inside the DART facil-itated shale gas enrichment,whereas the higher thermal maturity of the shales outside the DART pos-sibly led to the graphitization and collapse of some OM pores.Meanwhile,the overpressure of high-production wells inside the DART generally reflects better shale gas preservation,benefiting from the shale's self-sealing nature,"upper capping and lower plugging"configuration,and limited faults and microfractures.Considering these insights,we introduced a"ternary enrichment"model for the Qiongzhusi shale gas.Although the current high gas production of Z201 was found at the reservoir 3,two additional reservoirs were identified with significant potential,thus suggesting a"multilayer stereoscopic development"strategy in future shale gas exploration within the DART.
查看更多>>摘要：Top-down environmental policies aim to mitigate environmental risks but inevitably lead to economic losses due to the market entry or exit of enterprises.This study developed a universal dynamic agent-based supply chain model to achieve tradeoffs between environmental risk reduction and economic sus-tainability.The model was used to conduct high-resolution daily simulations of the dynamic shifts in enterprise operations and their cascading effects on supply chain networks.It includes production,con-sumption,and transportation agents,attributing economic features to supply chain components and cap-turing their interactions.It also accounts for adaptive responses to daily external shocks and replicates realistic firm behaviors.By coupling high spatial-temporal resolution firm-level data from 18 916 chemical enterprises,this study investigates the economic and environmental impacts of an environmen-tal policy resulting in the closure of 1800 chemical enterprises over three years.The results revealed a significant economic loss of 25.8 billion USD,ranging from 23.8 billion to 31.8 billion USD.Notably,over 80％of this loss was attributed to supply chain propagation.Counterfactual analyses indicated that imple-menting a staggered shutdown strategy prevented 18.8％of supply chain losses,highlighting the impor-tance of a gradual policy implementation to prevent abrupt supply chain disruptions.Furthermore,the study highlights the effectiveness of a multi-objective policy design in reducing economic losses(about 29％)and environmental risks(about 40％),substantially enhancing the efficiency of the environmental policy.The high-resolution simulations provide valuable insights for policy designers to formulate strategies with staggered implementation and multiple objectives to mitigate supply chain losses and environmental risks and ensure a sustainable future.
查看更多>>摘要：Concerns about the durability of transportation infrastructure due to freeze-thaw(F-T)cycles are particu-larly significant in the Chinese plateau region,where concrete aging and performance deterioration pose substantial challenges.The current national standards for the frost resistance design of concrete struc-tures are based predominantly on the coldest monthly average temperature and do not adequately address the comprehensive effects of the spatiotemporal variance,amplitude,and frequency of F-T cycles.To address this issue,this study introduced a spatiotemporal distribution model to analyze the long-term impact of F-T action on concrete structures by employing statistical analysis and spatial inter-polation techniques.Cluster analysis was applied to create a nationwide zonation of F-T action level from data on the freezing temperature,temperature difference,and the number of F-T cycles.Furthermore,this study explored the similarity between natural environmental conditions and laboratory-accelerated tests using hydraulic pressure and cumulative damage theories.A visualization platform that incorporates tools for meteorological data queries,environmental characteristic analyses,and F-T action similarity calculations was designed.This research lays theoretical groundwork and provides technical guidance for assessing service life and enhancing the quantitative durability design of concrete structures in the Chinese plateau region.
查看更多>>摘要：The 2280 km long Jinsha River has been blocked at least four times in the past 30 years.A landslide dam-ming hazard chain can endanger communities and infrastructures hundreds of kilometers downstream from the damming site in alpine gorges.Past damming events have resulted in severe consequences,demanding a thorough assessment of damming threats along the entire Jinsha River.This study digitizes the Jinsha River and visualizes its topographic,tectonic,hydrologic,and climate characteristics in detail.A two-stage full-probability method is proposed for assessing the damming threats along this river,mak-ing it possible to identify potential damming hotspots and high-priority zones for hazard mitigation.It is found that the upper reach of the Jinsha River poses the greatest damming threat,and the threat level gradually decreases downstream.Approximately 33.4％,36.7％,20.5％,and 9.4％of the entire length of the Jinsha River are classified as low,moderate,high,and very high threat levels,respectively.Compared with existing hydropower projects,future projects in the upper reach are more likely to be exposed to landslide damming.We highlight the value of basin-scale spatial threat analysis and envisage that our findings will promote more targeted local-scale risk assessments for potential damming hot-spots.These outcomes provide the basis for managing the risks of river damming and hydropower infras-tructure along the Jinsha River.
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