Professor Jun Li believes that the main etiology and pathogenesis of vascular dementia is the combination of phlegm and blood stasis.The symptoms include feeling faint and declined senses in organs of the head,caused ...Professor Jun Li believes that the main etiology and pathogenesis of vascular dementia is the combination of phlegm and blood stasis.The symptoms include feeling faint and declined senses in organs of the head,caused by mystery reason.To cure phlegm and blood stasis simultaneously,the therapy promotes the notion of“resolving phlegm and stimulating the circulation of blood,liberate brain orifices,”and treatments with the addition and removal of“Naotaitong Decoction,”which has an amazing clinical curative effect.This paper examines Professor Jun Li’s theoretical foundations and ideas from the syndrome differentiation and treatment of phlegm and blood stasis,systematically examines the curative effect and mechanism of Naotaitong Decoction in the treatment of vascular dementia,and examines the prescription and medication of typical cases for readers,in the hopes of providing guidance to clinical diagnosis and treatment of this disease.展开更多
Developing advanced electrocatalysts to convert CO_(2) into liquid fuels such as C_(2)H_(5)OH is critical for utilizing intermittent renewable energy.The formation of C_(2)H_(5)OH,however,is generally less favored com...Developing advanced electrocatalysts to convert CO_(2) into liquid fuels such as C_(2)H_(5)OH is critical for utilizing intermittent renewable energy.The formation of C_(2)H_(5)OH,however,is generally less favored compared with the other hydrocarbon products from Cu-based electrocatalysts.In this work,an alkanethiolmodified Cu_(2)O nanowire array(OTT-Cu_(2)O) was constructed with asymmetric Cu sites consisting of paired Cu-O and Cu-S motifs to overcome previous limitations of C_(2)H_(5)OH electrosynthesis via CO_(2)RR pathway.This catalyst achieves a high Faradaic efficiency of 45 % for CO_(2)-to-C_(2)H_(5)OH conversion at 300 m A/cm^(2),representing a more than two-fold enhancement over the Cu_(2)O electrode.Mechanistic investigations reveal that the Cu-S site exhibits distinct C-binding capability that stabilizes key intermediates(^(*)OCH_(2) and ^(*)CO),in contrast to the O-affinitive Cu-O site.The asymmetric S-Cu-O configuration promotes thermodynamically favorable asymmetric C-C coupling between ^(*)CO and ^(*)OCH_(2),forming the critical CO-OCH_(2) intermediate and facilitating C_(2)H_(5)OH production,as opposed to symmetric O-Cu-O sites that mainly generate HCOOH.This work offers an effective strategy for designing multi-active-site catalysts toward highly selective CO_(2) reduction to C_(2)H_(5)OH and provides fundamental insight into the reaction mechanism.展开更多
Peridynamics(PD)demonstrates unique advantages in addressing fracture problems,however,its nonlocality and meshfree discretization result in high computational and storage costs.Moreover,in its engineering application...Peridynamics(PD)demonstrates unique advantages in addressing fracture problems,however,its nonlocality and meshfree discretization result in high computational and storage costs.Moreover,in its engineering applications,the computational scale of classical GPU parallel schemes is often limited by the finite graphics memory of GPU devices.In the present study,we develop an efficient particle information management strategy based on the cell-linked list method and on this basis propose a subdomain-based GPU parallel scheme,which exhibits outstanding acceleration performance in specific compute kernels while significantly reducing graphics memory usage.Compared to the classical parallel scheme,the cell-linked list method facilitates efficient management of particle information within subdomains,enabling the proposed parallel scheme to effectively reduce graphics memory usage by optimizing the size and number of subdomains while significantly improving the speed of neighbor search.As demonstrated in PD examples,the proposed parallel scheme enhances the neighbor search efficiency dramatically and achieves a significant speedup relative to serial programs.For instance,without considering the time of data transmission,the proposed scheme achieves a remarkable speedup of nearly 1076.8×in one test case,due to its excellent computational efficiency in the neighbor search.Additionally,for 2D and 3D PD models with tens of millions of particles,the graphics memory usage can be reduced up to 83.6%and 85.9%,respectively.Therefore,this subdomain-based GPU parallel scheme effectively avoids graphics memory shortages while significantly improving the computational efficiency,providing new insights into studying more complex large-scale problems.展开更多
This study examined the relationship between loneliness and mobile phone addiction(MPA),and the mediating roles of social anxiety and self presentation in that relationship.The sample comprised 559 students(male=250,f...This study examined the relationship between loneliness and mobile phone addiction(MPA),and the mediating roles of social anxiety and self presentation in that relationship.The sample comprised 559 students(male=250,female=309,mean age=20.78 years,SD=1.13 years).Based on bias-corrected bootstrap method,our indicate loneliness to be associated with MPA of college students.Additionally,social anxiety and self-presentation,respectively,partially mediated the association between loneliness and college students’MPA.Specifically,as loneliness increased,both social anxiety and self-presentation rose,thereby increasing MPA.Social anxiety and self-presentation also sequentially mediated the relationship between loneliness and MPA among college students,such that greater loneliness heightened social anxiety,which subsequently enhanced self-presentation,ultimately resulting in increased MPA.These findings are consistent with Compensatory Internet Use Theory(CIUT).This study findings suggest for college students counselling and development services should alleviate loneliness and social anxiety through group activities,Cognitive-behavioral Therapy(CBT),and social skills training to foster belonging and reduce students’reliance on mobile phones.展开更多
The Jellium closed-shell model,a cornerstone of cluster science,has long guided the design of superatoms by dictating electron-counting rules.However,its reliance on precise control of cluster composition and electron...The Jellium closed-shell model,a cornerstone of cluster science,has long guided the design of superatoms by dictating electron-counting rules.However,its reliance on precise control of cluster composition and electron shell occupancy presents significant experimental challenges.Here,we introduce a ligation strategy that circumvents these limitations by demonstrating that the adiabatic electron affinity(AEA) of aluminum-based clusters,whether with filled or partially filled electron shells,can be dramatically enhanced through the attachment of organic Lewis acid ligands.It was evidenced that the AEA of PAl12can be significantly increased by 2.17 e V after the ligation of two ligands,indicating a remarkable improvement in its electron-accepting ability.This approach yields superhalogen species,offering a versatile and practical means to tune the electronic properties of clusters while preserving their superatomic states,independent of shell occupancy.Remarkably,this ligand-induced modulation is not confined to naked clusters but also extends to nano-confined systems,hinting at its broader applicability.Given the indispensable role of ligands in cluster synthesis,this strategy holds promise for advancing the field of condensed-phase superatom synthesis,potentially complementing traditional electron-counting rules in a broader range of applications.展开更多
Low-angle grain boundaries(LAGBs)are one of the solidification defects in single-crystal nickel-based superalloys and are detrimental to the mechanical properties.The formation of LAGBs is related to dendrite deformat...Low-angle grain boundaries(LAGBs)are one of the solidification defects in single-crystal nickel-based superalloys and are detrimental to the mechanical properties.The formation of LAGBs is related to dendrite deformation,while the mechanism has not been fully understood at the mesoscale.In this work,a model coupling dendrite growth,thermal-solutal-fluid flow,thermal stress and flow-induced dendrite deformation via cellular automaton-finite volume method and finite element method is developed to study the formation of LAGBs in single crystal superalloys.Results reveal that the bending of dendrites is primarily attributed to the thermal-solutal convection-induced dendrite deformation.The mechanical stress of dendrite deformation develops and stabilises as solidification proceeds.As the width of the mushy zone gets stable,stresses are built up and then dendritic elastoplastic bending occurs at some thin primary dendrites with the wider inter-dendritic space.There are three characteristic zones of stress distribution along the solidification direction:(i)no stress concentration in the fully solidified regions;(ii)stress developing in the primary dendrite bridging region,and(iii)stress decrease in the inter-dendritic uncontacted zone.The stresses reach maximum near the initial dendrite bridging position.The lower temperature gradients,the finer primary dendritic trunks and sudden reductions in local dendritic trunk radius jointly promote the elastoplastic deformation of the dendrites.Corresponding measures are suggested to reduce LAGBs.展开更多
In the era of green logistics,digital transformation has become an effective means for the logistics industry’s high-quality development.Using listed companies in China’s logistics industry from 2010 to 2021 as the ...In the era of green logistics,digital transformation has become an effective means for the logistics industry’s high-quality development.Using listed companies in China’s logistics industry from 2010 to 2021 as the research samples,this paper conducts an empirical test on the impact of the digital transformation of logistics enterprises on their green in-novation.Specifically,enterprise digital transformation indicators are constructed through the text analysis method,and the fixed-effects model is applied for analysis.The results indicate that the digital transformation of logistics enterprises has a significant promoting effect on their green innovation;the promoting effect of the digital transformation of logistics enterprises on green innovation is primarily achieved by easing corporate financing constraints and reducing corporate en-vironmental uncertainty;and the impact of digital transformation on green innovation is geographically heterogeneous.展开更多
Artificial intelligence(AI)serves as a key technology in global industrial transformation and technological restructuring and as the core driver of the fourth industrial revolution.Currently,deep learning techniques,s...Artificial intelligence(AI)serves as a key technology in global industrial transformation and technological restructuring and as the core driver of the fourth industrial revolution.Currently,deep learning techniques,such as convolutional neural networks,enable intelligent information collection in fields such as tongue and pulse diagnosis owing to their robust feature-processing capabilities.Natural language processing models,including long short-term memory and transformers,have been applied to traditional Chinese medicine(TCM)for diagnosis,syndrome differentiation,and prescription generation.Traditional machine learning algorithms,such as neural networks,support vector machines,and random forests,are also widely used in TCM diagnosis and treatment because of their strong regression and classification performance on small structured datasets.Future research on AI in TCM diagnosis and treatment may emphasize building large-scale,high-quality TCM datasets with unified criteria based on syndrome elements;identifying algorithms suited to TCM theoretical data distributions;and leveraging AI multimodal fusion and ensemble learning techniques for diverse raw features,such as images,text,and manually processed structured data,to increase the clinical efficacy of TCM diagnosis and treatment.展开更多
Chinese cabbage(Brassica rapa subsp.pekinensis)is a widely cultivated vegetable crop in Asia with significant economic importance(Li et al.,2024;Yu et al.,2024).As a potyvirus with the broad host range,turnip mosaic v...Chinese cabbage(Brassica rapa subsp.pekinensis)is a widely cultivated vegetable crop in Asia with significant economic importance(Li et al.,2024;Yu et al.,2024).As a potyvirus with the broad host range,turnip mosaic virus(TuMV)is a major pathogen affecting Chinese cabbages,leading to severe yield losses(Li et al.,2019).Traditional control measures have shown limited efficacy,and the long-term use of chemical pesticides has led to significant issues such as environmental pollution and pathogen resistance(Samara et al.,2021;Lu et al.,2022).Biologicallyderived pesticides have garnered considerable attention owing to their eco-friendly attributes(Ayilara et al.,2023).γ-Aminobutyric acid(GABA),initially discovered in potato tubers,has been proven to regulate immune responses and enhance resistance to fungal and bacterial pathogens by modulating reactive oxygen species and stress-related hormone signals(Tarkowski et al.,2020;Wang et al.,2025).But biologically-derived agents typically face challenges such as large particle size and instability,which limit their practical application and bioavailability(Daraban et al.,2023).展开更多
Basal cell carcinoma(BCC)and cutaneous squamous cell carcinoma(cSCC),as certain forms of nonmelanoma skin cancer(NMSC)or keratinocyte carcinoma,are the most common forms of malignant neoplasms worldwide(Sharp et al.,2...Basal cell carcinoma(BCC)and cutaneous squamous cell carcinoma(cSCC),as certain forms of nonmelanoma skin cancer(NMSC)or keratinocyte carcinoma,are the most common forms of malignant neoplasms worldwide(Sharp et al.,2024).BCC and cSCC have been identified as two major components of NMSC,comprising one-third of all malignancies(Burton et al.,2016).Generally speaking,patients with NMSC tend to have relatively favorable survival outcomes,while different histopathological subtypes of NMSC exhibit distinct biological behaviors(Stătescu et al.,2023).展开更多
The well-facilitated farmland projects(WFFPs)involve the typical sustainable intensification of farmland use and play a key role in raising food production in China.However,whether such WFFPs can enhance the nitrogen(...The well-facilitated farmland projects(WFFPs)involve the typical sustainable intensification of farmland use and play a key role in raising food production in China.However,whether such WFFPs can enhance the nitrogen(N)use efficiency and reduce environmental impacts is still unclear.Here,we examined the data from 502 valid questionnaires collected from WFFPs in the major grain-producing area,the Huang-Huai-Hai Region(HHHR)in China,with 429 samples for wheat,328 for maize,and 122 for rice.We identified gaps in N use efficiency(NUE)and N losses from the production of the three crops between the sampled WFFPs and counties based on the statistical data.The results showed that compared to the county-level(wheat,39.1%;maize,33.8%;rice,35.1%),the NUEs for wheat(55.2%),maize(52.1%),and rice(50.2%)in the WFFPs were significantly improved(P<0.05).In addition,the intensities of ammonia(NH3)volatilization(9.9-12.2 kg N ha–1),N leaching(6.5-16.9 kg N ha–1),and nitrous oxide(N2O)emissions(1.2-1.6 kg N ha–1)from crop production in the sampled WFFPs were significantly lower than the county averages(P<0.05).Simulations showed that if the N rates are reduced by 10.0,15.0,and 20.0%for the counties,the NUEs of wheat,maize,and rice in the HHHR will increase by 2.9-6.3,2.4-5.2,and 2.6-5.7%,respectively.If the N rate is reduced to the WFFP level in each county,the NUEs of the three crops will increase by 12.9-19.5%,and the N leaching,NH3,and N2O emissions will be reduced by 48.9-56.2,37.4-42.9,and 46.0-66.5%,respectively.Our findings highlight that efficient N management practices in sustainable intensive farmland have considerable potential for reducing environmental impacts.展开更多
Dissimilar joining of NiTi and stainless steel(SS)is important in biomedical applications but poses significant challenges due to brittle intermetallic compounds(IMCs)formation in the welds.Replacing harmful phases in...Dissimilar joining of NiTi and stainless steel(SS)is important in biomedical applications but poses significant challenges due to brittle intermetallic compounds(IMCs)formation in the welds.Replacing harmful phases in fusion welding cannot fully eliminate brittle IMCs and may introduce toxic elements,while the mixing restriction in solid-state welding increases the process complexity and results in large plastic deformation that degrades NiTi functional properties.In this work,we present a novel methodology that achieves a solid-state joined interface in NiTi-SS fusion welding(i.e.,resistance microwelding)through in-situ interfacial liquid control.By combining the advantages of both welding techniques,the current method produced NiTi-SS joints with superior strength,superelasticity and biocompatibility compared to NiTi joints or base metal.The ultrathin reaction layer at the solid-state joined interface contributed to a strong metallurgical bonding,while Joule heating effects and interfacial reactions enhanced superelasticity and biocompatibility of the joint.By demonstrating complete superelasticity on NiTi side,flexible deformation capacity on SS side,superior resistance to hydrogen embrittlement and electrochemical corrosion,and reduced Ni ion release and cytotoxicity,the welded joint shows great potential for the fabrication of multifunctional biomedical devices.Our work not only provides a comprehensive study of NiTi-SS joining under the biomedical background,but also introduces a new strategy for controlling material interface and dissimilar-metal welding process.展开更多
H_(2)O_(2)is an environmentally friendly oxidizing agent with minimal secondary pollution;however,its application has always been constrained by factors such as storage and transportation.In this study,we propose an i...H_(2)O_(2)is an environmentally friendly oxidizing agent with minimal secondary pollution;however,its application has always been constrained by factors such as storage and transportation.In this study,we propose an innovative method for storing and releasing H_(2)O_(2)using hydrogels.Commercial hydrogels(sodium polyacrylate)can undergo swelling and absorb H_(2)O_(2)in aqueous solutions,and the swollen hydrogel can continuously release H_(2)O_(2)under osmotic pressure.And the characteristics of osmotic pressure drive ensure the recyclability of hydrogel for H_(2)O_(2)storage.Experimental results demonstrate that H_(2)O_(2)can stably exist within the hydrogel for an extended period,and this strategy helps to avoid explosion the risk and potential environmental hazards during the transportation of H_(2)O_(2).Finally,experiments confirm that the hydrogel controlled sustained release of H_(2)O_(2)is effective in both Fenton reactions and the process of bacterial inactivation.This work introduces new ideas for the storage of H_(2)O_(2),and the sustained release of H_(2)O_(2)may have significant implications in the fields of healthcare,environmental science,catalysis,and beyond.展开更多
Organic compounds are important contributors to the optical properties and health effects of combustion-derived particles.However,the connection between optical properties and toxicity of combustion particles remains ...Organic compounds are important contributors to the optical properties and health effects of combustion-derived particles.However,the connection between optical properties and toxicity of combustion particles remains a matter of little concern.In this study,combustion particles were collected from 11 primary sources,including biomass burning,coal combustion,and vehicle exhaust.The extractable organic matter(EOM)in bituminous coal combustion particles shows the highest light-absorption,fluorescence properties,and toxicity among samples.Parallel factor(PARAFAC)analysis combined excitation−emission matrix(EEM)spectroscopy resolved 4 types of basic chromophore components in EOM.Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS)analysis further resolved∼800 molecules,predominantly aromatics(84%±4.6%),which showed positive correlations with the light-absorption,fluorescence properties and toxicity of EOM(p<0.05).Aromatics are inferred to be the intrinsic link between the optical properties and toxicity of EOM in combustion particles.Additionally,the benzene poly(carboxylic acid)s(BPCAs)method,which could identify and quantify fused benzene rings in EOM,further indicates the high condensation degree of aromatics is closely correlated with the lightabsorption,fluorescence properties of EOM.However,the toxicity of EOM may depend on the bay or fjord region of aromatics.These findings provide valuable insights into the light-absorption,fluorescence properties and toxicity of EOM in combustion particles.展开更多
Inspired by the remarkable surface wetting behavior of natural organisms,artificially designed superwettable systems have attracted significant attention from multidisciplinary scientists over the past two decades.Sta...Inspired by the remarkable surface wetting behavior of natural organisms,artificially designed superwettable systems have attracted significant attention from multidisciplinary scientists over the past two decades.Starch is an eco-friendly,nontoxic,and low-cost natural polymer that serves as an alternative to nonbiodegradable and/or bioincompatible synthetic polymers in these systems.This review explores the unique contributions of starch to superwettable systems from design principles to emerging applications.First,the fundamental theories and design principles underlying starch-involved superwettable systems are introduced.The specific design principles of these systems are comprehensively discussed from the aspects of intrinsic properties(e.g.,hydrophilicity,film-forming properties,adhesiveness,and thermal decomposition),dimensionality(e.g.,colloidal systems,zero-dimensional granules/particles,one-dimensional fibers,two-dimensional films/fibrous membranes/coatings,and three-dimensional fillers/porous materials/food textures),and biotransformation.It also provides an overview of their applications in functio nal biomaterials,oral delivery systems,emulsion polymerizatio n,packaging technology,food taste modulation,and water treatment,with particular emphasis on intelligent systems.Each section summarizes recent advancements,highlighting the chemical and structural features.Finally,the review considers prospects for these superwettable systems,focusing on underutilized starch attributes and technical challenges.展开更多
Traditional Internet of Things(IoT)architectures that rely on centralized servers for data management and decision-making are vulnerable to security threats and privacy leakage.To address this issue,blockchain has bee...Traditional Internet of Things(IoT)architectures that rely on centralized servers for data management and decision-making are vulnerable to security threats and privacy leakage.To address this issue,blockchain has been advocated for decentralized data management in a tamper-resistance,traceable,and transparent manner.However,a major issue that hinders the integration of blockchain and IoT lies in that,it is rather challenging for resource-constrained IoT devices to perform computation-intensive blockchain consensuses such as Proof-of-Work(PoW).Furthermore,the incentive mechanism of PoW pushes lightweight IoT nodes to aggregate their computing power to increase the possibility of successful block generation.Nevertheless,this eventually leads to the formation of computing power alliances,and significantly compromises the decentralization and security of BlockChain-aided IoT(BC-IoT)networks.To cope with these issues,we propose a lightweight consensus protocol for BC-IoT,called Proof-of-Trusted-Work(PoTW).The goal of the proposed consensus is to disincentivize the centralization of computing power and encourage the independent participation of lightweight IoT nodes in blockchain consensus.First,we put forth an on-chain reputation evaluation rule and a reputation chain for PoTW to enable the verifiability and traceability of nodes’reputations based on their contributions of computing power to the blockchain consensus,and we incorporate the multi-level block generation difficulty as a rewards for nodes to accumulate reputations.Second,we model the block generation process of PoTW and analyze the block throughput using the continuous time Markov chain.Additionally,we define and optimize the relative throughput gain to quantify and maximize the capability of PoTW that suppresses the computing power centralization(i.e.,centralization suppression).Furthermore,we investigate the impact of the computing power of the computing power alliance and the levels of block generation difficulty on the centralization suppression capability of PoTW.Finally,simulation results demonstrate the consistency of the analytical results in terms of block throughput.In particular,the results show that PoTW effectively reduces the block generation proportion of the computing power alliance compared with PoW,while simultaneously improving that of individual lightweight nodes.This indicates that PoTW is capable of suppressing the centralization of computing power to a certain degree.Moreover,as the levels of block generation difficulty in PoTW increase,its centralization suppression capability strengthens.展开更多
The gas kick represents a major risk in deepwater oil and gas exploration.Understanding the dynamics of gas kick evolution and the associated pressure response characteristics is critical for effective well control.In...The gas kick represents a major risk in deepwater oil and gas exploration.Understanding the dynamics of gas kick evolution and the associated pressure response characteristics is critical for effective well control.In this paper,we introduce a transient wellbore multiphase flow model specifically developed to simulate gas kick in deepwater dual-gradient drilling,incorporating a downhole separator.The model accounts for the variable mass flow within the annulus and heat exchange between the annular fluid and the formation.Using this model,we analyzed the multiphase flow and thermodynamic behavior during the gas kick.Simulation results reveal a progressive increase in bottom-hole temperature,underscoring its potential as a key indicator for gas kick early detection.Additionally,variable gradient parameters affect not only the annular equivalent circulating density(ECD)profile but also the evolution of the gas kick.The inclusion of a downhole separator alters the annular ECD profile,creating a“broken line”shape,which enhances adaptability to the multi-pressure systems typically encountered in deepwater forma-tion.By adjusting factors such as hollow sphere concentration,separator position,and separation effi-ciency,the annular ECD profile can be effectively customized.This study provides important theoretical insights and practical applications for utilizing dual-gradient drilling technology to address challenges in deepwater formation drilling.展开更多
Nickel-based single-crystal(SX)superalloys are the key metallic materials of aeroengines.However,thermomechanical deformation always occurs during the directional solidification of SX superalloys,negatively influencin...Nickel-based single-crystal(SX)superalloys are the key metallic materials of aeroengines.However,thermomechanical deformation always occurs during the directional solidification of SX superalloys,negatively influencing the SX structure.Casting deformation is simulated in most of the previous studies,whereas the direct simulation of dendritic thermomechanical deformation has been largely ignored,resulting in a lack of comprehensive understanding of this process.In this study,we systematically investigate dendritic thermomechanical deformation with a model coupled with dendrite growth,fluid flow,and thermomechanical deformation behavior.Results reveal that the dendritic thermomechanical deformation-induced dendrite bending is not randomly distributed but is mainly concentrated on the casting surface.The dendritic thermal stress increases as dendrite grows and accumulates after dendrite bridging.Transverse thermal contraction mainly occurs at the edge of casting in the corner,and axial thermal contraction is larger than transverse contraction.The high-stress region of the primary dendrite trunk is mainly distributed below the dendrite bridging near the solidified part,and the stress along the transverse direction reaches its maximum value on the casting surface.Stress concentrated on the casting surface is mainly attributed to variations in transverse temperature gradients caused by heat dissipation on the lateral mold wall,and inconsistent constraints in the lateral mold walls.展开更多
This study provides a thorough investigation into the vibration behavior and impulse response characteristics of composite honeycomb cylindrical shells filled with damping gel(DG-FHCSs).To address the limitations of e...This study provides a thorough investigation into the vibration behavior and impulse response characteristics of composite honeycomb cylindrical shells filled with damping gel(DG-FHCSs).To address the limitations of existing methods,a dynamic model is developed for both free and forced vibration scenarios.These models incorporate the virtual spring technology to accurately simulate a wide range of boundary conditions.Using the first-order shear deformation theory in conjunction with the Jacobi orthogonal polynomials,an energy expression is formulated,and the natural frequencies and mode shapes are determined via the Ritz method.Based on the Newmark-βmethod,the pulse response amplitudes and attenuation characteristics under various transient excitation loads are analyzed and evaluated.The accuracy of the theoretical model and the vibration suppression capability of the damping gel are experimentally validated.Furthermore,the effects of key structural parameters on the natural frequency and vibration response are systematically examined.展开更多
基金Shaanxi excellent talents training project of traditional Chinese medicine(Shaanxi Traditional Chinese Medicine Letter[2020]112)Project of Shaanxi Administration of traditional Chinese medicine(No.2021-ZZ-LC016).
文摘Professor Jun Li believes that the main etiology and pathogenesis of vascular dementia is the combination of phlegm and blood stasis.The symptoms include feeling faint and declined senses in organs of the head,caused by mystery reason.To cure phlegm and blood stasis simultaneously,the therapy promotes the notion of“resolving phlegm and stimulating the circulation of blood,liberate brain orifices,”and treatments with the addition and removal of“Naotaitong Decoction,”which has an amazing clinical curative effect.This paper examines Professor Jun Li’s theoretical foundations and ideas from the syndrome differentiation and treatment of phlegm and blood stasis,systematically examines the curative effect and mechanism of Naotaitong Decoction in the treatment of vascular dementia,and examines the prescription and medication of typical cases for readers,in the hopes of providing guidance to clinical diagnosis and treatment of this disease.
基金financial supports of the National Natural Science Foundation of China (NSFC,Nos.52394202,52476056,and 52301232)the Natural Science Foundation of Chongqing Province (No.2024NSCQ-MSX1109)。
文摘Developing advanced electrocatalysts to convert CO_(2) into liquid fuels such as C_(2)H_(5)OH is critical for utilizing intermittent renewable energy.The formation of C_(2)H_(5)OH,however,is generally less favored compared with the other hydrocarbon products from Cu-based electrocatalysts.In this work,an alkanethiolmodified Cu_(2)O nanowire array(OTT-Cu_(2)O) was constructed with asymmetric Cu sites consisting of paired Cu-O and Cu-S motifs to overcome previous limitations of C_(2)H_(5)OH electrosynthesis via CO_(2)RR pathway.This catalyst achieves a high Faradaic efficiency of 45 % for CO_(2)-to-C_(2)H_(5)OH conversion at 300 m A/cm^(2),representing a more than two-fold enhancement over the Cu_(2)O electrode.Mechanistic investigations reveal that the Cu-S site exhibits distinct C-binding capability that stabilizes key intermediates(^(*)OCH_(2) and ^(*)CO),in contrast to the O-affinitive Cu-O site.The asymmetric S-Cu-O configuration promotes thermodynamically favorable asymmetric C-C coupling between ^(*)CO and ^(*)OCH_(2),forming the critical CO-OCH_(2) intermediate and facilitating C_(2)H_(5)OH production,as opposed to symmetric O-Cu-O sites that mainly generate HCOOH.This work offers an effective strategy for designing multi-active-site catalysts toward highly selective CO_(2) reduction to C_(2)H_(5)OH and provides fundamental insight into the reaction mechanism.
基金Jun Li was supported by National Natural Science Foundation of China(No.:U2441215)Lisheng Liu and Xin Lai were supported by National Natural Science Foundation of China(No.:52494933).
文摘Peridynamics(PD)demonstrates unique advantages in addressing fracture problems,however,its nonlocality and meshfree discretization result in high computational and storage costs.Moreover,in its engineering applications,the computational scale of classical GPU parallel schemes is often limited by the finite graphics memory of GPU devices.In the present study,we develop an efficient particle information management strategy based on the cell-linked list method and on this basis propose a subdomain-based GPU parallel scheme,which exhibits outstanding acceleration performance in specific compute kernels while significantly reducing graphics memory usage.Compared to the classical parallel scheme,the cell-linked list method facilitates efficient management of particle information within subdomains,enabling the proposed parallel scheme to effectively reduce graphics memory usage by optimizing the size and number of subdomains while significantly improving the speed of neighbor search.As demonstrated in PD examples,the proposed parallel scheme enhances the neighbor search efficiency dramatically and achieves a significant speedup relative to serial programs.For instance,without considering the time of data transmission,the proposed scheme achieves a remarkable speedup of nearly 1076.8×in one test case,due to its excellent computational efficiency in the neighbor search.Additionally,for 2D and 3D PD models with tens of millions of particles,the graphics memory usage can be reduced up to 83.6%and 85.9%,respectively.Therefore,this subdomain-based GPU parallel scheme effectively avoids graphics memory shortages while significantly improving the computational efficiency,providing new insights into studying more complex large-scale problems.
基金supported by The Xingdian Talent Support Program Project(41112080006/015)Yunnan University Graduate Research Innovation Fund Project(KC-252512463).
文摘This study examined the relationship between loneliness and mobile phone addiction(MPA),and the mediating roles of social anxiety and self presentation in that relationship.The sample comprised 559 students(male=250,female=309,mean age=20.78 years,SD=1.13 years).Based on bias-corrected bootstrap method,our indicate loneliness to be associated with MPA of college students.Additionally,social anxiety and self-presentation,respectively,partially mediated the association between loneliness and college students’MPA.Specifically,as loneliness increased,both social anxiety and self-presentation rose,thereby increasing MPA.Social anxiety and self-presentation also sequentially mediated the relationship between loneliness and MPA among college students,such that greater loneliness heightened social anxiety,which subsequently enhanced self-presentation,ultimately resulting in increased MPA.These findings are consistent with Compensatory Internet Use Theory(CIUT).This study findings suggest for college students counselling and development services should alleviate loneliness and social anxiety through group activities,Cognitive-behavioral Therapy(CBT),and social skills training to foster belonging and reduce students’reliance on mobile phones.
基金supported by the National Natural Science Foundation of China (NSFC,Nos.12474274,92161101)the Innovation Project of Jinan Science and Technology Bureau (No.2021GXRC032)the Natural Science Foundation of Shandong Province (No.ZR2024MA091)。
文摘The Jellium closed-shell model,a cornerstone of cluster science,has long guided the design of superatoms by dictating electron-counting rules.However,its reliance on precise control of cluster composition and electron shell occupancy presents significant experimental challenges.Here,we introduce a ligation strategy that circumvents these limitations by demonstrating that the adiabatic electron affinity(AEA) of aluminum-based clusters,whether with filled or partially filled electron shells,can be dramatically enhanced through the attachment of organic Lewis acid ligands.It was evidenced that the AEA of PAl12can be significantly increased by 2.17 e V after the ligation of two ligands,indicating a remarkable improvement in its electron-accepting ability.This approach yields superhalogen species,offering a versatile and practical means to tune the electronic properties of clusters while preserving their superatomic states,independent of shell occupancy.Remarkably,this ligand-induced modulation is not confined to naked clusters but also extends to nano-confined systems,hinting at its broader applicability.Given the indispensable role of ligands in cluster synthesis,this strategy holds promise for advancing the field of condensed-phase superatom synthesis,potentially complementing traditional electron-counting rules in a broader range of applications.
基金sponsored by the National Natural Science Foundation of China(Grant Nos.52074182,52304406 and U23A20612)the Natural Science Foundation of Shanghai(Grant Nos.22ZR1430700 and 23TS1401900)+1 种基金the National Science and Technology Major Project(No.2017-VII-0008-0102)Neng Ren acknowledges the Startup Fund for Young Faculty at SJTU.
文摘Low-angle grain boundaries(LAGBs)are one of the solidification defects in single-crystal nickel-based superalloys and are detrimental to the mechanical properties.The formation of LAGBs is related to dendrite deformation,while the mechanism has not been fully understood at the mesoscale.In this work,a model coupling dendrite growth,thermal-solutal-fluid flow,thermal stress and flow-induced dendrite deformation via cellular automaton-finite volume method and finite element method is developed to study the formation of LAGBs in single crystal superalloys.Results reveal that the bending of dendrites is primarily attributed to the thermal-solutal convection-induced dendrite deformation.The mechanical stress of dendrite deformation develops and stabilises as solidification proceeds.As the width of the mushy zone gets stable,stresses are built up and then dendritic elastoplastic bending occurs at some thin primary dendrites with the wider inter-dendritic space.There are three characteristic zones of stress distribution along the solidification direction:(i)no stress concentration in the fully solidified regions;(ii)stress developing in the primary dendrite bridging region,and(iii)stress decrease in the inter-dendritic uncontacted zone.The stresses reach maximum near the initial dendrite bridging position.The lower temperature gradients,the finer primary dendritic trunks and sudden reductions in local dendritic trunk radius jointly promote the elastoplastic deformation of the dendrites.Corresponding measures are suggested to reduce LAGBs.
基金supported by the National Natural Science Foundation of China(72374061,72204243)the Ministry of Education’s Humanities and Social Science Research Youth Fund Project(20YJC630138,22YJC630056)+1 种基金Anhui Provincial Natural Science Foundation(2208085UD02)New Liberal Arts Fund Expansion Project of University of Science and Technology of China(FSSF-A-230317).
文摘In the era of green logistics,digital transformation has become an effective means for the logistics industry’s high-quality development.Using listed companies in China’s logistics industry from 2010 to 2021 as the research samples,this paper conducts an empirical test on the impact of the digital transformation of logistics enterprises on their green in-novation.Specifically,enterprise digital transformation indicators are constructed through the text analysis method,and the fixed-effects model is applied for analysis.The results indicate that the digital transformation of logistics enterprises has a significant promoting effect on their green innovation;the promoting effect of the digital transformation of logistics enterprises on green innovation is primarily achieved by easing corporate financing constraints and reducing corporate en-vironmental uncertainty;and the impact of digital transformation on green innovation is geographically heterogeneous.
基金supported by grants from the National Natural Science Foundation of China(Key Program)(No.82230124)Traditional Chinese Medicine Inheritance and Innovation“Ten million”talent project-Qihuang Project Chief Scientist Project(No.0201000401)+1 种基金State Administration of Traditional Chinese Medicine 2nd National Traditional Chinese Medicine Inheritance Studio Construction Project(Official Letter of the State Office of Traditional Chinese Medicine[2022]No.245)National Natural Science Foundation of China(General Program)(No.81974556).
文摘Artificial intelligence(AI)serves as a key technology in global industrial transformation and technological restructuring and as the core driver of the fourth industrial revolution.Currently,deep learning techniques,such as convolutional neural networks,enable intelligent information collection in fields such as tongue and pulse diagnosis owing to their robust feature-processing capabilities.Natural language processing models,including long short-term memory and transformers,have been applied to traditional Chinese medicine(TCM)for diagnosis,syndrome differentiation,and prescription generation.Traditional machine learning algorithms,such as neural networks,support vector machines,and random forests,are also widely used in TCM diagnosis and treatment because of their strong regression and classification performance on small structured datasets.Future research on AI in TCM diagnosis and treatment may emphasize building large-scale,high-quality TCM datasets with unified criteria based on syndrome elements;identifying algorithms suited to TCM theoretical data distributions;and leveraging AI multimodal fusion and ensemble learning techniques for diverse raw features,such as images,text,and manually processed structured data,to increase the clinical efficacy of TCM diagnosis and treatment.
基金supported by the National Natural Science Foundation of China(Grant Nos.32402564,32330096,32372631)Hebei Natural Science Foundation(Grant No.C2024204246)+1 种基金the Pinduoduo-China Agricultural University Research Fund(Grant No.PC2023B02018)the 2115 Talent Development Program of China Agricultural University.
文摘Chinese cabbage(Brassica rapa subsp.pekinensis)is a widely cultivated vegetable crop in Asia with significant economic importance(Li et al.,2024;Yu et al.,2024).As a potyvirus with the broad host range,turnip mosaic virus(TuMV)is a major pathogen affecting Chinese cabbages,leading to severe yield losses(Li et al.,2019).Traditional control measures have shown limited efficacy,and the long-term use of chemical pesticides has led to significant issues such as environmental pollution and pathogen resistance(Samara et al.,2021;Lu et al.,2022).Biologicallyderived pesticides have garnered considerable attention owing to their eco-friendly attributes(Ayilara et al.,2023).γ-Aminobutyric acid(GABA),initially discovered in potato tubers,has been proven to regulate immune responses and enhance resistance to fungal and bacterial pathogens by modulating reactive oxygen species and stress-related hormone signals(Tarkowski et al.,2020;Wang et al.,2025).But biologically-derived agents typically face challenges such as large particle size and instability,which limit their practical application and bioavailability(Daraban et al.,2023).
基金supported by the National Natural Science Foundation of China(No.82003372)the Medical and Health Technology Project of Zhejiang Province(No.2024KY984),China.
文摘Basal cell carcinoma(BCC)and cutaneous squamous cell carcinoma(cSCC),as certain forms of nonmelanoma skin cancer(NMSC)or keratinocyte carcinoma,are the most common forms of malignant neoplasms worldwide(Sharp et al.,2024).BCC and cSCC have been identified as two major components of NMSC,comprising one-third of all malignancies(Burton et al.,2016).Generally speaking,patients with NMSC tend to have relatively favorable survival outcomes,while different histopathological subtypes of NMSC exhibit distinct biological behaviors(Stătescu et al.,2023).
基金supported by the National Key Research and Development Program of China(2022YFB3903505)the National Natural Science Foundation of China(72221002)。
文摘The well-facilitated farmland projects(WFFPs)involve the typical sustainable intensification of farmland use and play a key role in raising food production in China.However,whether such WFFPs can enhance the nitrogen(N)use efficiency and reduce environmental impacts is still unclear.Here,we examined the data from 502 valid questionnaires collected from WFFPs in the major grain-producing area,the Huang-Huai-Hai Region(HHHR)in China,with 429 samples for wheat,328 for maize,and 122 for rice.We identified gaps in N use efficiency(NUE)and N losses from the production of the three crops between the sampled WFFPs and counties based on the statistical data.The results showed that compared to the county-level(wheat,39.1%;maize,33.8%;rice,35.1%),the NUEs for wheat(55.2%),maize(52.1%),and rice(50.2%)in the WFFPs were significantly improved(P<0.05).In addition,the intensities of ammonia(NH3)volatilization(9.9-12.2 kg N ha–1),N leaching(6.5-16.9 kg N ha–1),and nitrous oxide(N2O)emissions(1.2-1.6 kg N ha–1)from crop production in the sampled WFFPs were significantly lower than the county averages(P<0.05).Simulations showed that if the N rates are reduced by 10.0,15.0,and 20.0%for the counties,the NUEs of wheat,maize,and rice in the HHHR will increase by 2.9-6.3,2.4-5.2,and 2.6-5.7%,respectively.If the N rate is reduced to the WFFP level in each county,the NUEs of the three crops will increase by 12.9-19.5%,and the N leaching,NH3,and N2O emissions will be reduced by 48.9-56.2,37.4-42.9,and 46.0-66.5%,respectively.Our findings highlight that efficient N management practices in sustainable intensive farmland have considerable potential for reducing environmental impacts.
基金Coherent Cu-rich nanoprecipitates:Achieving both high strength and superior magnetic properties in non-oriented silicon steels。
文摘Dissimilar joining of NiTi and stainless steel(SS)is important in biomedical applications but poses significant challenges due to brittle intermetallic compounds(IMCs)formation in the welds.Replacing harmful phases in fusion welding cannot fully eliminate brittle IMCs and may introduce toxic elements,while the mixing restriction in solid-state welding increases the process complexity and results in large plastic deformation that degrades NiTi functional properties.In this work,we present a novel methodology that achieves a solid-state joined interface in NiTi-SS fusion welding(i.e.,resistance microwelding)through in-situ interfacial liquid control.By combining the advantages of both welding techniques,the current method produced NiTi-SS joints with superior strength,superelasticity and biocompatibility compared to NiTi joints or base metal.The ultrathin reaction layer at the solid-state joined interface contributed to a strong metallurgical bonding,while Joule heating effects and interfacial reactions enhanced superelasticity and biocompatibility of the joint.By demonstrating complete superelasticity on NiTi side,flexible deformation capacity on SS side,superior resistance to hydrogen embrittlement and electrochemical corrosion,and reduced Ni ion release and cytotoxicity,the welded joint shows great potential for the fabrication of multifunctional biomedical devices.Our work not only provides a comprehensive study of NiTi-SS joining under the biomedical background,but also introduces a new strategy for controlling material interface and dissimilar-metal welding process.
基金supported by National Natural Science Foundation of China(Nos.22325602,22176060)Program of Shanghai Academic/Technology Research Leader(No.23XD1421000)+2 种基金Project supported by Shanghai Municipal Science and Technology Major Project(No.2018SHZDZX03)the Program of Introducing Talents of Discipline to Universities(No.B16017)Science and Technology Commission of Shanghai Municipality(No.20DZ2250400)。
文摘H_(2)O_(2)is an environmentally friendly oxidizing agent with minimal secondary pollution;however,its application has always been constrained by factors such as storage and transportation.In this study,we propose an innovative method for storing and releasing H_(2)O_(2)using hydrogels.Commercial hydrogels(sodium polyacrylate)can undergo swelling and absorb H_(2)O_(2)in aqueous solutions,and the swollen hydrogel can continuously release H_(2)O_(2)under osmotic pressure.And the characteristics of osmotic pressure drive ensure the recyclability of hydrogel for H_(2)O_(2)storage.Experimental results demonstrate that H_(2)O_(2)can stably exist within the hydrogel for an extended period,and this strategy helps to avoid explosion the risk and potential environmental hazards during the transportation of H_(2)O_(2).Finally,experiments confirm that the hydrogel controlled sustained release of H_(2)O_(2)is effective in both Fenton reactions and the process of bacterial inactivation.This work introduces new ideas for the storage of H_(2)O_(2),and the sustained release of H_(2)O_(2)may have significant implications in the fields of healthcare,environmental science,catalysis,and beyond.
基金supported by the National Natural Science Foundation of China(No.42030715 and 42192511)the Alliance of International Science Organizations(ANSO-CRKP-2021-05)+1 种基金the Basic and Applied Basic Research Foundation of Guangdong Province(2023B0303000007,2023B1515020067 and 2022A1515011271)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(2022359).
文摘Organic compounds are important contributors to the optical properties and health effects of combustion-derived particles.However,the connection between optical properties and toxicity of combustion particles remains a matter of little concern.In this study,combustion particles were collected from 11 primary sources,including biomass burning,coal combustion,and vehicle exhaust.The extractable organic matter(EOM)in bituminous coal combustion particles shows the highest light-absorption,fluorescence properties,and toxicity among samples.Parallel factor(PARAFAC)analysis combined excitation−emission matrix(EEM)spectroscopy resolved 4 types of basic chromophore components in EOM.Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS)analysis further resolved∼800 molecules,predominantly aromatics(84%±4.6%),which showed positive correlations with the light-absorption,fluorescence properties and toxicity of EOM(p<0.05).Aromatics are inferred to be the intrinsic link between the optical properties and toxicity of EOM in combustion particles.Additionally,the benzene poly(carboxylic acid)s(BPCAs)method,which could identify and quantify fused benzene rings in EOM,further indicates the high condensation degree of aromatics is closely correlated with the lightabsorption,fluorescence properties of EOM.However,the toxicity of EOM may depend on the bay or fjord region of aromatics.These findings provide valuable insights into the light-absorption,fluorescence properties and toxicity of EOM in combustion particles.
基金financially supported by the National Key Research and Development Program of China(2023YFD1600600 and 2021YFD1600105-03)the Postdoctoral Fellowship Program of China Postdoctoral Science Foundation(GZB20240665)+1 种基金the Special Funding for Postdoctoral Research Projects in Zhejiang(ZJ2024044)the China Postdoctoral Science Foundation(2024M762848)。
文摘Inspired by the remarkable surface wetting behavior of natural organisms,artificially designed superwettable systems have attracted significant attention from multidisciplinary scientists over the past two decades.Starch is an eco-friendly,nontoxic,and low-cost natural polymer that serves as an alternative to nonbiodegradable and/or bioincompatible synthetic polymers in these systems.This review explores the unique contributions of starch to superwettable systems from design principles to emerging applications.First,the fundamental theories and design principles underlying starch-involved superwettable systems are introduced.The specific design principles of these systems are comprehensively discussed from the aspects of intrinsic properties(e.g.,hydrophilicity,film-forming properties,adhesiveness,and thermal decomposition),dimensionality(e.g.,colloidal systems,zero-dimensional granules/particles,one-dimensional fibers,two-dimensional films/fibrous membranes/coatings,and three-dimensional fillers/porous materials/food textures),and biotransformation.It also provides an overview of their applications in functio nal biomaterials,oral delivery systems,emulsion polymerizatio n,packaging technology,food taste modulation,and water treatment,with particular emphasis on intelligent systems.Each section summarizes recent advancements,highlighting the chemical and structural features.Finally,the review considers prospects for these superwettable systems,focusing on underutilized starch attributes and technical challenges.
基金supported in part by National Key R&D Program of China(Grant No.2021YFB1714100)in part by the National Natural Science Foundation of China(NSFC)under Grant 62371239+5 种基金in part by the the Program of Science and Technology Cooperation of Nanjing with International/Hong Kong,Macao and Taiwan(Grant No.202401019)in part by the Guangdong Basic and Applied Basic Research Foundation(Grant No.2024A1515012407)in part by the the Research Center for FinTech and Digital-Intelligent Management at Shenzhen University,in part by the National Natural Science Foundation of China under Grant 62271192in part by the Equipment Pre-Research Joint Research Program of Ministry of Education under Grant 8091B032129in part by the Major Science and Technology Projects of Longmen Laboratory under Grant 231100220300 and 231100220200in part by the Central Plains Leading Talent in Scientific and Technological Innovation Program under Grant 244200510048.
文摘Traditional Internet of Things(IoT)architectures that rely on centralized servers for data management and decision-making are vulnerable to security threats and privacy leakage.To address this issue,blockchain has been advocated for decentralized data management in a tamper-resistance,traceable,and transparent manner.However,a major issue that hinders the integration of blockchain and IoT lies in that,it is rather challenging for resource-constrained IoT devices to perform computation-intensive blockchain consensuses such as Proof-of-Work(PoW).Furthermore,the incentive mechanism of PoW pushes lightweight IoT nodes to aggregate their computing power to increase the possibility of successful block generation.Nevertheless,this eventually leads to the formation of computing power alliances,and significantly compromises the decentralization and security of BlockChain-aided IoT(BC-IoT)networks.To cope with these issues,we propose a lightweight consensus protocol for BC-IoT,called Proof-of-Trusted-Work(PoTW).The goal of the proposed consensus is to disincentivize the centralization of computing power and encourage the independent participation of lightweight IoT nodes in blockchain consensus.First,we put forth an on-chain reputation evaluation rule and a reputation chain for PoTW to enable the verifiability and traceability of nodes’reputations based on their contributions of computing power to the blockchain consensus,and we incorporate the multi-level block generation difficulty as a rewards for nodes to accumulate reputations.Second,we model the block generation process of PoTW and analyze the block throughput using the continuous time Markov chain.Additionally,we define and optimize the relative throughput gain to quantify and maximize the capability of PoTW that suppresses the computing power centralization(i.e.,centralization suppression).Furthermore,we investigate the impact of the computing power of the computing power alliance and the levels of block generation difficulty on the centralization suppression capability of PoTW.Finally,simulation results demonstrate the consistency of the analytical results in terms of block throughput.In particular,the results show that PoTW effectively reduces the block generation proportion of the computing power alliance compared with PoW,while simultaneously improving that of individual lightweight nodes.This indicates that PoTW is capable of suppressing the centralization of computing power to a certain degree.Moreover,as the levels of block generation difficulty in PoTW increase,its centralization suppression capability strengthens.
基金supported by the Postdoctoral Fellow-ship Program of CPSF(Grant No.GZC20233105)the Science Foundation of China University of Petroleum,Beijing(Grant No.2462024XKBH006)+2 种基金the China Postdoctoral Science Foundation(Grant No.2024M753615)the Major Scientific Research Instrument Development Program of National Natural Science Foundation of China(Grant No.52227804)the Youth Science Foundation Program of National Natural Science Foundation of China(Grant No.52404012).
文摘The gas kick represents a major risk in deepwater oil and gas exploration.Understanding the dynamics of gas kick evolution and the associated pressure response characteristics is critical for effective well control.In this paper,we introduce a transient wellbore multiphase flow model specifically developed to simulate gas kick in deepwater dual-gradient drilling,incorporating a downhole separator.The model accounts for the variable mass flow within the annulus and heat exchange between the annular fluid and the formation.Using this model,we analyzed the multiphase flow and thermodynamic behavior during the gas kick.Simulation results reveal a progressive increase in bottom-hole temperature,underscoring its potential as a key indicator for gas kick early detection.Additionally,variable gradient parameters affect not only the annular equivalent circulating density(ECD)profile but also the evolution of the gas kick.The inclusion of a downhole separator alters the annular ECD profile,creating a“broken line”shape,which enhances adaptability to the multi-pressure systems typically encountered in deepwater forma-tion.By adjusting factors such as hollow sphere concentration,separator position,and separation effi-ciency,the annular ECD profile can be effectively customized.This study provides important theoretical insights and practical applications for utilizing dual-gradient drilling technology to address challenges in deepwater formation drilling.
基金financially sponsored by the National Natural Science Foundation of China(Nos.U2441268 and 52304406)the Natural Science Foundation of Shanghai,China(No.23TS1401900)+2 种基金the Science Foundation of Aeronautics(PSSFA),China(No.2024Z053057002)the Science and Technology Cooperation Program of Shanghai Jiao Tong University in Inner Mongolia Autonomous Region-Action Plan of Shanghai Jiao Tong University for“Revitalizing Inner Mongolia through Science and Technology”,ChinaLuwei Yang would like to thank the financial support from the Chinese Scholarship Council(No.202306230337).
文摘Nickel-based single-crystal(SX)superalloys are the key metallic materials of aeroengines.However,thermomechanical deformation always occurs during the directional solidification of SX superalloys,negatively influencing the SX structure.Casting deformation is simulated in most of the previous studies,whereas the direct simulation of dendritic thermomechanical deformation has been largely ignored,resulting in a lack of comprehensive understanding of this process.In this study,we systematically investigate dendritic thermomechanical deformation with a model coupled with dendrite growth,fluid flow,and thermomechanical deformation behavior.Results reveal that the dendritic thermomechanical deformation-induced dendrite bending is not randomly distributed but is mainly concentrated on the casting surface.The dendritic thermal stress increases as dendrite grows and accumulates after dendrite bridging.Transverse thermal contraction mainly occurs at the edge of casting in the corner,and axial thermal contraction is larger than transverse contraction.The high-stress region of the primary dendrite trunk is mainly distributed below the dendrite bridging near the solidified part,and the stress along the transverse direction reaches its maximum value on the casting surface.Stress concentrated on the casting surface is mainly attributed to variations in transverse temperature gradients caused by heat dissipation on the lateral mold wall,and inconsistent constraints in the lateral mold walls.
基金supported by the National Natural Science Foundation of China(Nos.12472005 and 52175079)the Aerospace Science Foundation of China(No.2022Z009050002)+2 种基金the Key Laboratory of Vibration and Control of Aero-Propulsion SystemMinistry of Education of China(No.VCAME201603)the Tai-Hang Laboratory Program(No.AK023)。
文摘This study provides a thorough investigation into the vibration behavior and impulse response characteristics of composite honeycomb cylindrical shells filled with damping gel(DG-FHCSs).To address the limitations of existing methods,a dynamic model is developed for both free and forced vibration scenarios.These models incorporate the virtual spring technology to accurately simulate a wide range of boundary conditions.Using the first-order shear deformation theory in conjunction with the Jacobi orthogonal polynomials,an energy expression is formulated,and the natural frequencies and mode shapes are determined via the Ritz method.Based on the Newmark-βmethod,the pulse response amplitudes and attenuation characteristics under various transient excitation loads are analyzed and evaluated.The accuracy of the theoretical model and the vibration suppression capability of the damping gel are experimentally validated.Furthermore,the effects of key structural parameters on the natural frequency and vibration response are systematically examined.
