The controlled assembly of nanomaterials has demon-strated significant potential in advancing technological devices.However,achieving highly efficient and low-loss assembly technique for nanomate-rials,enabling the cr...The controlled assembly of nanomaterials has demon-strated significant potential in advancing technological devices.However,achieving highly efficient and low-loss assembly technique for nanomate-rials,enabling the creation of hierarchical structures with distinctive func-tionalities,remains a formidable challenge.Here,we present a method for nanomaterial assembly enhanced by ionic liquids,which enables the fabrication of highly stable,flexible,and transparent electrodes featuring an organized layered structure.The utilization of hydrophobic and non-volatile ionic liquids facilitates the production of stable interfaces with water,effectively preventing the sedimentation of 1D/2D nanomaterials assembled at the interface.Furthermore,the interfacially assembled nanomaterial monolayer exhibits an alternate self-climbing behavior,enabling layer-by-layer transfer and the formation of a well-ordered MXene-wrapped silver nanowire network film.The resulting composite film not only demonstrates exceptional photoelectric performance with a sheet resistance of 9.4Ωsq^(-1) and 93%transmittance,but also showcases remarkable environmental stability and mechanical flexibility.Particularly noteworthy is its application in transparent electromagnetic interference shielding materials and triboelectric nanogenerator devices.This research introduces an innovative approach to manufacture and tailor functional devices based on ordered nanomaterials.展开更多
For the porous‐membrane‐based osmotic energy generator,the potential synergistic enhancement mechanism of various key parameters is still controversial,especially because optimizing the trade‐off between permeabili...For the porous‐membrane‐based osmotic energy generator,the potential synergistic enhancement mechanism of various key parameters is still controversial,especially because optimizing the trade‐off between permeability and selectivity is still a challenge.Here,to construct a permeability and selectivity synergistically enhanced osmotic energy generator,the twodimensional porous membranes with tunable charge density are prepared by inserting sulfonated polyether sulfone into graphene oxide.Influences of charge density and pore size on the ion transport are explored,and the ionic behaviors in the channel are calculated by numerical simulations.The mechanism of ion transport in the process is studied in depth,and the fundamental principles of energy conversion are revealed.The results demonstrate that charge density and pore size should be matched to construct the optimal ion channel.This collaborative enhancement strategy of permeability and selectivity has significantly improved the output power in osmotic energy generation;compared to the pure graphene oxide membrane,the composite membrane presents almost 20 times improvement.展开更多
Biomimetic materials that use natural wisdom to solve practical problems are developing rapidly.The trend for systematic biomimicry is towards in-situ characterization of naturalcreatures with high spatial resolutions...Biomimetic materials that use natural wisdom to solve practical problems are developing rapidly.The trend for systematic biomimicry is towards in-situ characterization of naturalcreatures with high spatial resolutions.Furthermore,rapid reconstruction of digital twin models with the same complex features as the prototype is indispensable.However,it faces bottlenecks and limits in fast characterization and fabrication,precise parameter optimization,geometricdeviations control,and quality prediction.To solve these challenges,here,we demonstrate astate-of-the-art method taking advantage of micro-computed tomography and three-dimensional printing for the fast characterization of the pitcher plant Nepenthes x ventrata and fabrication of its biomimetic model to obtain a superior drainage controller with multiscale structures withprecise surface morphology optimization and geometric deviation control.Thefilm-rupture-based drainage dynamic and mechanisms are characterized by x-ray and high-speed videography,which determines the crucial structures for unique directionaldrainage.Then the optimized artificial pitchers are further developed into sustained drainage devices with novel applications,such as detection,reaction,and smoke control.展开更多
Perovskite oxides has been attracted much attention as high-performance oxygen carriers for chemical looping reforming of methane,but they are easily inactivated by the presence of trace H_(2)S.Here,we propose to modu...Perovskite oxides has been attracted much attention as high-performance oxygen carriers for chemical looping reforming of methane,but they are easily inactivated by the presence of trace H_(2)S.Here,we propose to modulate both the activity and resistance to sulfur poisoning by dual substitution of Mo and Ni ions with the Fe-sites of LaFeO_(3)perovskite.It is found that partial substitution of Ni for Fe substantially improves the activity of LaFeO_(3)perovskite,while Ni particles prefer to grow and react with H_(2)S during the long-term successive redox process,resulting in the deactivation of oxygen carriers.With the presence of Mo in LaNi_(0.05)Fe_(0.95)O_(3−σ)perovskite,H_(2)S preferentially reacts with Mo to generate MoS_(2),and then the CO_(2)oxidation can regenerate Mo via removing sulfur.In addition,Mo can inhibit the accumulation and growth of Ni,which helps to improve the redox stability of oxygen carriers.The LaNi_(0.05)Mo_(0.07)Fe_(0.88)O_(3−σ)oxygen carrier exhibits stable and excellent performance,with the CH_(4)conversion higher than 90%during the 50 redox cycles in the presence of 50 ppm H_(2)S at 800℃.This work highlights a synergistic effect in the perovskite oxides induced by dual substitution of different cations for the development of high-performance oxygen carriers with excellent sulfur tolerance.展开更多
Galloping cheetahs,climbing mountain goats,and load hauling horses all show desirable locomotion capability,which motivates the development of quadruped robots.Among various quadruped robots,hydraulically driven quadr...Galloping cheetahs,climbing mountain goats,and load hauling horses all show desirable locomotion capability,which motivates the development of quadruped robots.Among various quadruped robots,hydraulically driven quadruped robots show great potential in unstructured environments due to their discrete landing positions and large payloads.As the most critical movement unit of a quadruped robot,the limb leg unit(LLU)directly affects movement speed and reliability,and requires a compact and lightweight design.Inspired by the dexterous skeleton–muscle systems of cheetahs and humans,this paper proposes a highly integrated bionic actuator system for a better dynamic performance of an LLU.We propose that a cylinder barrel with multiple element interfaces and internal smooth channels is realized using metal additive manufacturing,and hybrid lattice structures are introduced into the lightweight design of the piston rod.In addition,additive manufacturing and topology optimization are incorporated to reduce the redundant material of the structural parts of the LLU.The mechanical properties of the actuator system are verified by numerical simulation and experiments,and the power density of the actuators is far greater than that of cheetah muscle.The mass of the optimized LLU is reduced by 24.5%,and the optimized LLU shows better response time performance when given a step signal,and presents a good trajectory tracking ability with the increase in motion frequency.展开更多
The fluid’s viscosity significantly affects the performance of a centrifugal pump.The entropy production method and leakage are employed to analyze the performance changes under various viscosities by numerical simul...The fluid’s viscosity significantly affects the performance of a centrifugal pump.The entropy production method and leakage are employed to analyze the performance changes under various viscosities by numerical simulation and validated by experiments.The results showed that increasing viscosity reduces both the pump head and efficiency.In addition,the optimal operating point shifts to the left.Leakage is influenced by vortex distribution in the front chamber and boundary layer thickness in wear-ring clearance,leading to an initial increase and subsequent decrease in leakage with increasing viscosity.The total entropy production Spro,Total inside the pump rises with increasing viscosity.The different mechanisms dominate under varying conditions:Turbulent dissipation dominates at low viscosity.Under high-viscosity conditions,energy loss is primarily caused by direct dissipation Spro,D and wall entropy production Spro,W.This study provides a deeper and more objective understanding of the energy characteristics of centrifugal pumps handling fluids of various viscosity,potentially aiding in optimizing pump design and improving energy conversion efficiency.展开更多
The challenges posed by energy and environmental issues have forced mankind to explore and utilize unconventional energy sources.It is imperative to convert the abundant coalbed gas(CBG)into high value-added products,...The challenges posed by energy and environmental issues have forced mankind to explore and utilize unconventional energy sources.It is imperative to convert the abundant coalbed gas(CBG)into high value-added products,i.e.,selective and efficient conversion of methane from CBG.Methane activation,known as the“holy grail”,poses a challenge to the design and development of catalysts.The structural complexity of the active metal on the carrier is of particular concern.In this work,we have studied the nucleation growth of small Co clusters(up to Co_(6))on the surface of CeO_(2)(110)using density functional theory,from which a stable loaded Co/CeO_(2)(110)structure was selected to investigate the methane activation mechanism.Despite the relatively small size of the selected Co clusters,the obtained Co_(x)/CeO_(2)(110)exhibits interesting properties.The optimized Co_(5)/CeO_(2)(110)structure was selected as the optimal structure to study the activation mechanism of methane due to its competitive electronic structure,adsorption energy and binding energy.The energy barriers for the stepwise dissociation of methane to form CH3^(*),CH2^(*),CH^(*),and C^(*)radical fragments are 0.44,0.55,0.31,and 1.20 eV,respectively,indicating that CH^(*)dissociative dehydrogenation is the rate-determining step for the system under investigation here.This fundamental study of metal-support interactions based on Co growth on the CeO_(2)(110)surface contributes to the understanding of the essence of Co/CeO_(2) catalysts with promising catalytic behavior.It provides theoretical guidance for better designing the optimal Co/CeO_(2) catalyst for tailored catalytic reactions.展开更多
This article examines the soft soil roadbed reinforcement technology for widened sections of highways in a specific project.It provides an overview of the project,the principles of soft soil roadbed reinforcement tech...This article examines the soft soil roadbed reinforcement technology for widened sections of highways in a specific project.It provides an overview of the project,the principles of soft soil roadbed reinforcement technology for wide sections,and its practical application.The analysis aims to offer guidance on applying soft soil roadbed wide section reinforcement technology and enhancing the overall quality of similar projects.展开更多
In this paper,the geological condition of the right-side slope of the K114+694–K115+162 section of Yong-tai-wen Expressway is investigated and analyzed with the results showing that the strength of rock mass is the m...In this paper,the geological condition of the right-side slope of the K114+694–K115+162 section of Yong-tai-wen Expressway is investigated and analyzed with the results showing that the strength of rock mass is the main contributor to the stability of the slope.Then,two widening schemes are proposed,which are the steep slope with strong support and the gentle slope with general support schemes.The static/slope module of MIDAS GTS finite element analysis software and the strength reduction method were used to compare the two schemes.The results show that the steep slope with a strong support scheme has obvious advantages in land requisition,environmental protection,and safety and is more suitable for reconstructing and expanding the highway slope.展开更多
TGF-Objective:To investigate the effect of postgraduate Shengsui Jiangu Capsule on tumor necrosis factors TNF-α,transforming growth factor TGF-β1 and empty bone lacuna in rats with alcoholic osteoporosis.Method:120 ...TGF-Objective:To investigate the effect of postgraduate Shengsui Jiangu Capsule on tumor necrosis factors TNF-α,transforming growth factor TGF-β1 and empty bone lacuna in rats with alcoholic osteoporosis.Method:120 SD rats were randomly divided into 4 groups,30 rats in each group:blank group,model group,western medicine control group and traditional Chinese medicine intervention group.Liquor gavage was used to model the disease,except for the blank group.The western medicine control group was gavaged with a suspension of calcium carbonate and afad3,while the Chinese medicine intervention group was gavaged with a suspension of Shengsui Jiangu capsules combined with 0.9%saline solution injection.The values of TNF-αand TGF-β1 in femora were measured after 8,12,and 16 weeks of intervention.After dissecting out the femoral head using the HE(hematoxylin-eosin staining)staining method,the bone lacunae were observed under a light microscope,and the empty bone lacunae rate was calculated for intergroup comparison.Results:Compared with the blank group,the model group had a significantly higher percentage of TNF-αand empty bone lacunae,and a significantly lower percentage of TGF-β1(P<0.01).Compared with the model group,the rates of TNF-αand empty bone lacunae in the western medicine control group and the Chinese medicine intervention group were significantly decreased,and TGF-β1 was significantly increased(P<0.01).The traditional Chinese medicine intervention group was more effective than the western medicine control group(P<0.05).Conclusion:Shengsui Jiangu capsule attenuates the expression of TNF-α,enhances the expression of TGF-β1,decreases the rate of empty bone lacunae,and achieves a protective effect against alcoholic osteoporosis in rats with alcoholic osteoporosis.展开更多
The rational synergy of chemical composition and spatial nanostructures of electrode materials play important roles in high-performance energy storage devices.Here,we designed pea-like MoS_(2)@NiS_(1.03)-carbon hollow...The rational synergy of chemical composition and spatial nanostructures of electrode materials play important roles in high-performance energy storage devices.Here,we designed pea-like MoS_(2)@NiS_(1.03)-carbon hollow nanofibers using a simple electrospinning and thermal treatment method.The hierarchical hollow nanofiber is composed of a nitrogen-doped carbon-coated NiS_(1.03) tube wall,in which pea-like uniformly discrete MoS_(2) nanoparticles are enclosed.As a sodium-ion battery electrode material,the MoS_(2)@NiS_(1.03)-carbon hollow nanofibers have abundant diphasic heterointerfaces,a conductive network,and appropriate volume variation-buffering spaces,which can facilitate ion diffusion kinetics,shorten the diffusion path of electrons/ion,and buffer volume expansion during Na^(+)insertion/extraction.It shows outstanding rate capacity and long-cycle performance in a sodium-ion battery.This heterogeneous hollow nanoarchitectures designing enlightens an efficacious strategy to boost the capacity and long-life stability of sodium storage performance of electrode materials.展开更多
The extraction of lithium from salt lakes or seawater has attracted worldwide attention because of the explosive growth of global demand for lithium products. The LiMn_(2)O_(4)-based electrochemical lithium recovery s...The extraction of lithium from salt lakes or seawater has attracted worldwide attention because of the explosive growth of global demand for lithium products. The LiMn_(2)O_(4)-based electrochemical lithium recovery system is one of the strongest candidates for commercial application due to its high inserted capacity and low energy consumption. However, the surface orientation of LiMn_(2)O_(4)that facilitates Li diffusion happens to be prone to manganese dissolution making it a great challenge to obtain high lithium inserted capacity and long life simultaneously. Herein, we address this problem by designing a truncated octahedral LiMn_(2)O_(4)(Tr-oh LMO) in which the dominant(111) facets minimize Mn dissolution while a small portion of(100) facets facilitate the Li diffusion. Thus, this Tr-oh LMO-based electrochemical lithium recovery system shows excellent Li recovery performance with high inserted capacity(20.25 mg g^(-1)per cycle) in simulated brine. In addition, the dissolution rate of manganese per 30 cycles is only 0.44% and the capacity maintained 85% of the initial after 30 cycles. These promising findings accelerate the practical application of LiMn_(2)O_(4)in electrochemical lithium recovery.展开更多
The global carbon neutrality strategy brings a wave of rechargeable lithium‐ion batteries technique development and induces an ever-growing consumption and demand for lithium(Li).Among all the Li exploitation,extract...The global carbon neutrality strategy brings a wave of rechargeable lithium‐ion batteries technique development and induces an ever-growing consumption and demand for lithium(Li).Among all the Li exploitation,extracting Li from spent LIBs would be a strategic and perspective approach,especially with the low energy consumption and eco-friendly membrane separation method.However,current membrane separation systems mainly focus on monotonous membrane design and structure optimization,and rarely further consider the coordination of inherent structure and applied external field,resulting in limited ion transport.Here,we propose a heterogeneous nanofluidic membrane as a platform for coupling multi-external fields(i.e.,lightinduced heat,electrical,and concentration gradient fields)to construct the multi-field-coupled synergistic ion transport system(MSITS)for Li-ion extraction from spent LIBs.The Li flux of the MSITS reaches 367.4 mmol m^(−2)h^(−1),even higher than the sum flux of those applied individual fields,reflecting synergistic enhancement for ion transport of the multi-field-coupled effect.Benefiting from the adaptation of membrane structure and multi-external fields,the proposed system exhibits ultrahigh selectivity with a Li^(+)/Co^(2+)factor of 216,412,outperforming previous reports.MSITS based on nanofluidic membrane proves to be a promising ion transport strategy,as it could accelerate ion transmembrane transport and alleviate the ion concentration polarization effect.This work demonstrated a collaborative system equipped with an optimized membrane for high-efficient Li extraction,providing an expanded strategy to investigate the other membrane-based applications of their common similarities in core concepts.展开更多
The deeply buried Lower Cambrian Longwangmiao Formation and Upper Ediacaran Dengying Formation from the Sichuan Basin,China,have a total natural gas reserve up to 3×10^(12)m^(3).The complex diagenetic evolution a...The deeply buried Lower Cambrian Longwangmiao Formation and Upper Ediacaran Dengying Formation from the Sichuan Basin,China,have a total natural gas reserve up to 3×10^(12)m^(3).The complex diagenetic evolution and their impacts on the present-day reservoir quality have not been systematically elucidated,hampering the current exploration.Crucially,the integration and comparation diagenetic study on these two formations,which may be able to shed new lights on reservoir formation mechanism,are yet to be systemically evaluated.By compiling geochemistry data,including carbonate U-Pb ages and petrophysics data,coupled with new petrology,trace elements,and strontium isotope data,of various types of diagenetic carbonates,this study aims to decipher the potential links between diagenesis and reservoir development of both formations.Intriguingly,similar diagenetic sequence,which contains five distinctive dolomite phases,is established in both formations.The matrix dolomite(D1)and early dolomite cement(D2)were likely formed by reflux dolomitization,as inferred by their nearly syn-depositional U-Pb ages and elevatedδ^(18)O caused by seawater evaporation.The subsequent moderate burial dolomite cement(D3)was most plausibly the product of burial compaction as indicated by its lighterδ^(18)O and slightly younger U-Pb ages compared with D1 and D2.Whereas deep burial dolomite cements(D4 and D5)yield markedly depletedδ^(18)O,elevated ^(87)Sr/^(86)Sr,along with much younger U-Pb ages and higher precipitation temperatures,suggesting that they were likely linked to hydrothermal fluids.Despite the wide occurrence of meteoric and organic acids leaching and thermochemical sulfate reduction,they may have only played a subsidiary role on these reservoirs development.Instead,superior reservoir quality is tightly linked to tectonics as inferred by higher reservoir quality closely related to the well-developed fractures and faults filled with abundant hydrothermal minerals.Notably,good reservoirs in both formations are mainly attributed to high permeability caused by tectonics.Hence,this new contribution emphasizes the crucial role of tectonics on spatially explicit reservoir prediction of deep to ultra-deep(up to>8000 m)carbonates in the Sichuan Basin,as well as other sedimentary basin analogues in China.展开更多
Dear Editor,Recent advances in military technology have led to the development of sophisticated and intelligent weapons, which increase mortality and morbidity. Since the advent of highexplosion weapons, "shock w...Dear Editor,Recent advances in military technology have led to the development of sophisticated and intelligent weapons, which increase mortality and morbidity. Since the advent of highexplosion weapons, "shock wave" has surpassed "shrapnel" and become the most important injurious component in conventional combat. Traumatic brain injury(TBI) is a leading cause of disability and death among military personnel and civilians during wartime[1]. Clinically, its symptoms and indications vary depending on the location and severity of the injury. The most frequently observed symptoms included altered consciousness and local dysfunction.展开更多
基金This work was supported by the National Natural Science Foundation of China(nos.21988102,and 22305026)the China Postdoctoral Science Foundation(2019M650433).
文摘The controlled assembly of nanomaterials has demon-strated significant potential in advancing technological devices.However,achieving highly efficient and low-loss assembly technique for nanomate-rials,enabling the creation of hierarchical structures with distinctive func-tionalities,remains a formidable challenge.Here,we present a method for nanomaterial assembly enhanced by ionic liquids,which enables the fabrication of highly stable,flexible,and transparent electrodes featuring an organized layered structure.The utilization of hydrophobic and non-volatile ionic liquids facilitates the production of stable interfaces with water,effectively preventing the sedimentation of 1D/2D nanomaterials assembled at the interface.Furthermore,the interfacially assembled nanomaterial monolayer exhibits an alternate self-climbing behavior,enabling layer-by-layer transfer and the formation of a well-ordered MXene-wrapped silver nanowire network film.The resulting composite film not only demonstrates exceptional photoelectric performance with a sheet resistance of 9.4Ωsq^(-1) and 93%transmittance,but also showcases remarkable environmental stability and mechanical flexibility.Particularly noteworthy is its application in transparent electromagnetic interference shielding materials and triboelectric nanogenerator devices.This research introduces an innovative approach to manufacture and tailor functional devices based on ordered nanomaterials.
基金Natural Science Foundation of Jilin Province,Grant/Award Number:YDZJ202101ZYTS002National Natural Science Foundation of China,Grant/Award Number:52003099+1 种基金Capital Construction Fund of Jilin Province,Grant/Award Number:2021C039‐1Fundamental Research Funds for the Central Universities。
文摘For the porous‐membrane‐based osmotic energy generator,the potential synergistic enhancement mechanism of various key parameters is still controversial,especially because optimizing the trade‐off between permeability and selectivity is still a challenge.Here,to construct a permeability and selectivity synergistically enhanced osmotic energy generator,the twodimensional porous membranes with tunable charge density are prepared by inserting sulfonated polyether sulfone into graphene oxide.Influences of charge density and pore size on the ion transport are explored,and the ionic behaviors in the channel are calculated by numerical simulations.The mechanism of ion transport in the process is studied in depth,and the fundamental principles of energy conversion are revealed.The results demonstrate that charge density and pore size should be matched to construct the optimal ion channel.This collaborative enhancement strategy of permeability and selectivity has significantly improved the output power in osmotic energy generation;compared to the pure graphene oxide membrane,the composite membrane presents almost 20 times improvement.
基金provided by the National sKey R&D Program of China(2021YFA0716701)the National Natural Science Foundation of China(22005014,.22275007,22102204)+1 种基金Beihang University’s Young Talents(No.KG16164901)Open Foundation of the State Key Laboratory of Precision Measuring Technology and Instruments(No.pilab2106)。
文摘Biomimetic materials that use natural wisdom to solve practical problems are developing rapidly.The trend for systematic biomimicry is towards in-situ characterization of naturalcreatures with high spatial resolutions.Furthermore,rapid reconstruction of digital twin models with the same complex features as the prototype is indispensable.However,it faces bottlenecks and limits in fast characterization and fabrication,precise parameter optimization,geometricdeviations control,and quality prediction.To solve these challenges,here,we demonstrate astate-of-the-art method taking advantage of micro-computed tomography and three-dimensional printing for the fast characterization of the pitcher plant Nepenthes x ventrata and fabrication of its biomimetic model to obtain a superior drainage controller with multiscale structures withprecise surface morphology optimization and geometric deviation control.Thefilm-rupture-based drainage dynamic and mechanisms are characterized by x-ray and high-speed videography,which determines the crucial structures for unique directionaldrainage.Then the optimized artificial pitchers are further developed into sustained drainage devices with novel applications,such as detection,reaction,and smoke control.
基金financially supported by the National Natural Science Foundation of China (Nos. 52174279, U2202251, and 52266008)Applied Basic Research Program of Yunnan Province for Distinguished Young Scholars (No. 202201AV070004)+1 种基金Central Guiding Local Science and Technology Development Fund (No. 202207AA110001)the Yunnan Fundamental Research Projects (No. 202301AU070027, 202401AT070388)
文摘Perovskite oxides has been attracted much attention as high-performance oxygen carriers for chemical looping reforming of methane,but they are easily inactivated by the presence of trace H_(2)S.Here,we propose to modulate both the activity and resistance to sulfur poisoning by dual substitution of Mo and Ni ions with the Fe-sites of LaFeO_(3)perovskite.It is found that partial substitution of Ni for Fe substantially improves the activity of LaFeO_(3)perovskite,while Ni particles prefer to grow and react with H_(2)S during the long-term successive redox process,resulting in the deactivation of oxygen carriers.With the presence of Mo in LaNi_(0.05)Fe_(0.95)O_(3−σ)perovskite,H_(2)S preferentially reacts with Mo to generate MoS_(2),and then the CO_(2)oxidation can regenerate Mo via removing sulfur.In addition,Mo can inhibit the accumulation and growth of Ni,which helps to improve the redox stability of oxygen carriers.The LaNi_(0.05)Mo_(0.07)Fe_(0.88)O_(3−σ)oxygen carrier exhibits stable and excellent performance,with the CH_(4)conversion higher than 90%during the 50 redox cycles in the presence of 50 ppm H_(2)S at 800℃.This work highlights a synergistic effect in the perovskite oxides induced by dual substitution of different cations for the development of high-performance oxygen carriers with excellent sulfur tolerance.
基金The work is supported by the National Natural Science Foundation of China(Nos.U21A20124 and 52205059)the Key Research and Development Program of Zhejiang Province(No.2022C01039)。
文摘Galloping cheetahs,climbing mountain goats,and load hauling horses all show desirable locomotion capability,which motivates the development of quadruped robots.Among various quadruped robots,hydraulically driven quadruped robots show great potential in unstructured environments due to their discrete landing positions and large payloads.As the most critical movement unit of a quadruped robot,the limb leg unit(LLU)directly affects movement speed and reliability,and requires a compact and lightweight design.Inspired by the dexterous skeleton–muscle systems of cheetahs and humans,this paper proposes a highly integrated bionic actuator system for a better dynamic performance of an LLU.We propose that a cylinder barrel with multiple element interfaces and internal smooth channels is realized using metal additive manufacturing,and hybrid lattice structures are introduced into the lightweight design of the piston rod.In addition,additive manufacturing and topology optimization are incorporated to reduce the redundant material of the structural parts of the LLU.The mechanical properties of the actuator system are verified by numerical simulation and experiments,and the power density of the actuators is far greater than that of cheetah muscle.The mass of the optimized LLU is reduced by 24.5%,and the optimized LLU shows better response time performance when given a step signal,and presents a good trajectory tracking ability with the increase in motion frequency.
基金supported by the National Natural Science Foundation of China(Grant Nos.52079058 and 52209113)the Natural Science Foundation of Jiangsu Province(Grant Nos.BK20230011 and BK20220544)+1 种基金China Postdoctoral Science Foundation(Grant No.2023M731367)Postgraduate Research&Practice Innovation Program of Jiangsu Province(Grant No.KYCX23_3698).
文摘The fluid’s viscosity significantly affects the performance of a centrifugal pump.The entropy production method and leakage are employed to analyze the performance changes under various viscosities by numerical simulation and validated by experiments.The results showed that increasing viscosity reduces both the pump head and efficiency.In addition,the optimal operating point shifts to the left.Leakage is influenced by vortex distribution in the front chamber and boundary layer thickness in wear-ring clearance,leading to an initial increase and subsequent decrease in leakage with increasing viscosity.The total entropy production Spro,Total inside the pump rises with increasing viscosity.The different mechanisms dominate under varying conditions:Turbulent dissipation dominates at low viscosity.Under high-viscosity conditions,energy loss is primarily caused by direct dissipation Spro,D and wall entropy production Spro,W.This study provides a deeper and more objective understanding of the energy characteristics of centrifugal pumps handling fluids of various viscosity,potentially aiding in optimizing pump design and improving energy conversion efficiency.
基金National Natural Science Foundation of China(52174279)Analysis and Testing Foundation of Kunming University of Science and Technology(2022M20202202138)Yunnan Fundamental Research Projects(202301AU070027).
文摘The challenges posed by energy and environmental issues have forced mankind to explore and utilize unconventional energy sources.It is imperative to convert the abundant coalbed gas(CBG)into high value-added products,i.e.,selective and efficient conversion of methane from CBG.Methane activation,known as the“holy grail”,poses a challenge to the design and development of catalysts.The structural complexity of the active metal on the carrier is of particular concern.In this work,we have studied the nucleation growth of small Co clusters(up to Co_(6))on the surface of CeO_(2)(110)using density functional theory,from which a stable loaded Co/CeO_(2)(110)structure was selected to investigate the methane activation mechanism.Despite the relatively small size of the selected Co clusters,the obtained Co_(x)/CeO_(2)(110)exhibits interesting properties.The optimized Co_(5)/CeO_(2)(110)structure was selected as the optimal structure to study the activation mechanism of methane due to its competitive electronic structure,adsorption energy and binding energy.The energy barriers for the stepwise dissociation of methane to form CH3^(*),CH2^(*),CH^(*),and C^(*)radical fragments are 0.44,0.55,0.31,and 1.20 eV,respectively,indicating that CH^(*)dissociative dehydrogenation is the rate-determining step for the system under investigation here.This fundamental study of metal-support interactions based on Co growth on the CeO_(2)(110)surface contributes to the understanding of the essence of Co/CeO_(2) catalysts with promising catalytic behavior.It provides theoretical guidance for better designing the optimal Co/CeO_(2) catalyst for tailored catalytic reactions.
文摘This article examines the soft soil roadbed reinforcement technology for widened sections of highways in a specific project.It provides an overview of the project,the principles of soft soil roadbed reinforcement technology for wide sections,and its practical application.The analysis aims to offer guidance on applying soft soil roadbed wide section reinforcement technology and enhancing the overall quality of similar projects.
文摘In this paper,the geological condition of the right-side slope of the K114+694–K115+162 section of Yong-tai-wen Expressway is investigated and analyzed with the results showing that the strength of rock mass is the main contributor to the stability of the slope.Then,two widening schemes are proposed,which are the steep slope with strong support and the gentle slope with general support schemes.The static/slope module of MIDAS GTS finite element analysis software and the strength reduction method were used to compare the two schemes.The results show that the steep slope with a strong support scheme has obvious advantages in land requisition,environmental protection,and safety and is more suitable for reconstructing and expanding the highway slope.
基金Joint Orientation Program of the Heilongjiang Nature Foundation(No.LH2020H086)Chinese Medicine Council of Heilongjiang(No.ZHY10-W22)。
文摘TGF-Objective:To investigate the effect of postgraduate Shengsui Jiangu Capsule on tumor necrosis factors TNF-α,transforming growth factor TGF-β1 and empty bone lacuna in rats with alcoholic osteoporosis.Method:120 SD rats were randomly divided into 4 groups,30 rats in each group:blank group,model group,western medicine control group and traditional Chinese medicine intervention group.Liquor gavage was used to model the disease,except for the blank group.The western medicine control group was gavaged with a suspension of calcium carbonate and afad3,while the Chinese medicine intervention group was gavaged with a suspension of Shengsui Jiangu capsules combined with 0.9%saline solution injection.The values of TNF-αand TGF-β1 in femora were measured after 8,12,and 16 weeks of intervention.After dissecting out the femoral head using the HE(hematoxylin-eosin staining)staining method,the bone lacunae were observed under a light microscope,and the empty bone lacunae rate was calculated for intergroup comparison.Results:Compared with the blank group,the model group had a significantly higher percentage of TNF-αand empty bone lacunae,and a significantly lower percentage of TGF-β1(P<0.01).Compared with the model group,the rates of TNF-αand empty bone lacunae in the western medicine control group and the Chinese medicine intervention group were significantly decreased,and TGF-β1 was significantly increased(P<0.01).The traditional Chinese medicine intervention group was more effective than the western medicine control group(P<0.05).Conclusion:Shengsui Jiangu capsule attenuates the expression of TNF-α,enhances the expression of TGF-β1,decreases the rate of empty bone lacunae,and achieves a protective effect against alcoholic osteoporosis in rats with alcoholic osteoporosis.
基金financially supported by the National Natural Science Foundation of China(NSFC)(Grant Nos.22175007,21975007,52172080,and 22005012)the National Natural Science Foundation for Outstanding Youth Foundation,the Fundamental Research Funds for the Central Universities,the National Program for Support of Top-notch Young Professionalsthe 111 project(Grant No.B14009).
文摘The rational synergy of chemical composition and spatial nanostructures of electrode materials play important roles in high-performance energy storage devices.Here,we designed pea-like MoS_(2)@NiS_(1.03)-carbon hollow nanofibers using a simple electrospinning and thermal treatment method.The hierarchical hollow nanofiber is composed of a nitrogen-doped carbon-coated NiS_(1.03) tube wall,in which pea-like uniformly discrete MoS_(2) nanoparticles are enclosed.As a sodium-ion battery electrode material,the MoS_(2)@NiS_(1.03)-carbon hollow nanofibers have abundant diphasic heterointerfaces,a conductive network,and appropriate volume variation-buffering spaces,which can facilitate ion diffusion kinetics,shorten the diffusion path of electrons/ion,and buffer volume expansion during Na^(+)insertion/extraction.It shows outstanding rate capacity and long-cycle performance in a sodium-ion battery.This heterogeneous hollow nanoarchitectures designing enlightens an efficacious strategy to boost the capacity and long-life stability of sodium storage performance of electrode materials.
基金supported by the National Natural Science Foundation of China (21878133,21908082,22178154)the Natural Science Foundation of Jiangsu Province(BK20190854)+1 种基金the China Postdoctoral Science Foundation(2020M671364,2021M701472)the Science&Technology Foundation of Zhenjiang (GY2020027)。
文摘The extraction of lithium from salt lakes or seawater has attracted worldwide attention because of the explosive growth of global demand for lithium products. The LiMn_(2)O_(4)-based electrochemical lithium recovery system is one of the strongest candidates for commercial application due to its high inserted capacity and low energy consumption. However, the surface orientation of LiMn_(2)O_(4)that facilitates Li diffusion happens to be prone to manganese dissolution making it a great challenge to obtain high lithium inserted capacity and long life simultaneously. Herein, we address this problem by designing a truncated octahedral LiMn_(2)O_(4)(Tr-oh LMO) in which the dominant(111) facets minimize Mn dissolution while a small portion of(100) facets facilitate the Li diffusion. Thus, this Tr-oh LMO-based electrochemical lithium recovery system shows excellent Li recovery performance with high inserted capacity(20.25 mg g^(-1)per cycle) in simulated brine. In addition, the dissolution rate of manganese per 30 cycles is only 0.44% and the capacity maintained 85% of the initial after 30 cycles. These promising findings accelerate the practical application of LiMn_(2)O_(4)in electrochemical lithium recovery.
基金supported by the National Key R&D Program of China(2022YFB3805904,2022YFB3805900)the National Natural Science Foundation of China(22122207,21988102,21905287)CAS Project for Young Scientists in Basic Research(YSBR-039).
文摘The global carbon neutrality strategy brings a wave of rechargeable lithium‐ion batteries technique development and induces an ever-growing consumption and demand for lithium(Li).Among all the Li exploitation,extracting Li from spent LIBs would be a strategic and perspective approach,especially with the low energy consumption and eco-friendly membrane separation method.However,current membrane separation systems mainly focus on monotonous membrane design and structure optimization,and rarely further consider the coordination of inherent structure and applied external field,resulting in limited ion transport.Here,we propose a heterogeneous nanofluidic membrane as a platform for coupling multi-external fields(i.e.,lightinduced heat,electrical,and concentration gradient fields)to construct the multi-field-coupled synergistic ion transport system(MSITS)for Li-ion extraction from spent LIBs.The Li flux of the MSITS reaches 367.4 mmol m^(−2)h^(−1),even higher than the sum flux of those applied individual fields,reflecting synergistic enhancement for ion transport of the multi-field-coupled effect.Benefiting from the adaptation of membrane structure and multi-external fields,the proposed system exhibits ultrahigh selectivity with a Li^(+)/Co^(2+)factor of 216,412,outperforming previous reports.MSITS based on nanofluidic membrane proves to be a promising ion transport strategy,as it could accelerate ion transmembrane transport and alleviate the ion concentration polarization effect.This work demonstrated a collaborative system equipped with an optimized membrane for high-efficient Li extraction,providing an expanded strategy to investigate the other membrane-based applications of their common similarities in core concepts.
基金supported by grants from the National Natural Science Foundation of China(41972149,41890843).
文摘The deeply buried Lower Cambrian Longwangmiao Formation and Upper Ediacaran Dengying Formation from the Sichuan Basin,China,have a total natural gas reserve up to 3×10^(12)m^(3).The complex diagenetic evolution and their impacts on the present-day reservoir quality have not been systematically elucidated,hampering the current exploration.Crucially,the integration and comparation diagenetic study on these two formations,which may be able to shed new lights on reservoir formation mechanism,are yet to be systemically evaluated.By compiling geochemistry data,including carbonate U-Pb ages and petrophysics data,coupled with new petrology,trace elements,and strontium isotope data,of various types of diagenetic carbonates,this study aims to decipher the potential links between diagenesis and reservoir development of both formations.Intriguingly,similar diagenetic sequence,which contains five distinctive dolomite phases,is established in both formations.The matrix dolomite(D1)and early dolomite cement(D2)were likely formed by reflux dolomitization,as inferred by their nearly syn-depositional U-Pb ages and elevatedδ^(18)O caused by seawater evaporation.The subsequent moderate burial dolomite cement(D3)was most plausibly the product of burial compaction as indicated by its lighterδ^(18)O and slightly younger U-Pb ages compared with D1 and D2.Whereas deep burial dolomite cements(D4 and D5)yield markedly depletedδ^(18)O,elevated ^(87)Sr/^(86)Sr,along with much younger U-Pb ages and higher precipitation temperatures,suggesting that they were likely linked to hydrothermal fluids.Despite the wide occurrence of meteoric and organic acids leaching and thermochemical sulfate reduction,they may have only played a subsidiary role on these reservoirs development.Instead,superior reservoir quality is tightly linked to tectonics as inferred by higher reservoir quality closely related to the well-developed fractures and faults filled with abundant hydrothermal minerals.Notably,good reservoirs in both formations are mainly attributed to high permeability caused by tectonics.Hence,this new contribution emphasizes the crucial role of tectonics on spatially explicit reservoir prediction of deep to ultra-deep(up to>8000 m)carbonates in the Sichuan Basin,as well as other sedimentary basin analogues in China.
文摘Dear Editor,Recent advances in military technology have led to the development of sophisticated and intelligent weapons, which increase mortality and morbidity. Since the advent of highexplosion weapons, "shock wave" has surpassed "shrapnel" and become the most important injurious component in conventional combat. Traumatic brain injury(TBI) is a leading cause of disability and death among military personnel and civilians during wartime[1]. Clinically, its symptoms and indications vary depending on the location and severity of the injury. The most frequently observed symptoms included altered consciousness and local dysfunction.