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Journal of Northeast Agricultural University (English Edition)Instruction to Authors
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《Journal of Northeast Agricultural University(English Edition)》 2025年第1期F0003-F0003,共1页
Aims and Scope Journal of Northeast Agricultural University(English Edition)is a comprehensive academic journal on agricultural sciences sponsored by Northeast Agricultural University and distributed worldwide.It is a... Aims and Scope Journal of Northeast Agricultural University(English Edition)is a comprehensive academic journal on agricultural sciences sponsored by Northeast Agricultural University and distributed worldwide.It is a peer reviewed journal published quarterly and mainly publishes review and research articles that reflect the latest achievements on crop science,horticulture,plant protection,resource and environment,animal science,veterinary medicine,agricultural engineering and technology,agricultural water conservancy,life science,biotechnology and food science. 展开更多
关键词 agricultural sciences HORTICULTURE plant protection review research articles crop science water co peer reviewed journal resource environment
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Journal of Northeast Agricultural University(English Edition) Instruction to Authors
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《Journal of Northeast Agricultural University(English Edition)》 2025年第2期F0003-F0003,共1页
Aims and Scope Journal of Northeast Agricultural University(English Edition)is a comprehensive academic journal on agricultural sciences sponsored by Northeast Agricultural University and distributed worldwide.It is a... Aims and Scope Journal of Northeast Agricultural University(English Edition)is a comprehensive academic journal on agricultural sciences sponsored by Northeast Agricultural University and distributed worldwide.It is a peer reviewed journal published quarterly and mainly publishes review and research articles that reflect the latest achievements on crop science,horticulture,plant protection,resource and environment,animal science,veterinary medicine,agricultural engineering and technology,agricultural water conservancy,life science,biotechnology and food science. 展开更多
关键词 agricultural sciences HORTICULTURE plant protection review research articles crop science water co animal science peer reviewed journal
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High-thermal free vibration analysis of functionally graded microplates using a new finite element formulation based on TSDT and MSCT
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作者 Huu Trong Dang Nhan Thinh Hoang +2 位作者 Quoc Hoa Pham Trung Thanh Tran Huy Gia Luong 《Defence Technology(防务技术)》 2025年第2期131-149,共19页
Recent advancements in additive manufacturing(AM)have revolutionized the design and production of complex engineering microstructures.Despite these advancements,their mathematical modeling and computational analysis r... Recent advancements in additive manufacturing(AM)have revolutionized the design and production of complex engineering microstructures.Despite these advancements,their mathematical modeling and computational analysis remain significant challenges.This research aims to develop an effective computational method for analyzing the free vibration of functionally graded(FG)microplates under high temperatures while resting on a Pasternak foundation(PF).This formulation leverages a new thirdorder shear deformation theory(new TSDT)for improved accuracy without requiring shear correction factors.Additionally,the modified couple stress theory(MCST)is incorporated to account for sizedependent effects in microplates.The PF is characterized by two parameters including spring stiffness(k_(w))and shear layer stiffness(k_(s)).To validate the proposed method,the results obtained are compared with those of the existing literature.Furthermore,numerical examples explore the influence of various factors on the high-temperature free vibration of FG microplates.These factors include the length scale parameter(l),geometric dimensions,material properties,and the presence of the elastic foundation.The findings significantly enhance our comprehension of the free vibration of FG microplates in high thermal environments.In addition,the findings significantly enhance our comprehension of the free vibration of FG microplates in high thermal environments.In addition,the results of this research will have great potential in military and defense applications such as components of submarines,fighter aircraft,and missiles. 展开更多
关键词 Microplates functionally graded material Finite element method Modified couple stress theory New TSDT High-thermal free vibration Pasternak foundation
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Novel multifunctional epoxy based graphitic carbon nitride/silanized TiO_(2) nanocomposite as protective coatings for steel surface against corrosion and flame in the shipping industry
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作者 XAVIER Joseph Raj 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第10期3394-3422,共29页
The chemical compound 3-(N-ethylamino)isobutyl)trimethoxysilane(EAMS)modified titanium dioxide(TiO_(2)),producing EAMS-TiO_(2),which was encased in graphitic carbon nitride(GCN)and integrated into epoxy resin(EP).The ... The chemical compound 3-(N-ethylamino)isobutyl)trimethoxysilane(EAMS)modified titanium dioxide(TiO_(2)),producing EAMS-TiO_(2),which was encased in graphitic carbon nitride(GCN)and integrated into epoxy resin(EP).The protective properties of mild steel coated with this nanocomposite in a marine environment were assessedusing electrochemical techniques.Thermogravimetric analysis(TGA)and Cone calorimetry tests demonstrated thatGCN/EAMS-TiO_(2)significantly enhanced the flame retardancy of the epoxy coating,reducing peak heat release rate(PHRR)and total heat release(THR)values by 88%and 70%,respectively,compared to pure EP.Salt spray testsindicated reduced water absorption and improved corrosion resistance.The optimal concentration of 0.6 wt%GCNEAMS/TiO_(2)yielded the highest resistance,with the nanocomposite achieving a coating resistance of 7.50×10^(10)Ω·cm^(2)after 28 d in seawater.The surface resistance of EP-GCN/EAMS-TiO_(2)was over 99.9 times higher than pure EP after onehour in seawater.SECM analysis showed the lowest ferrous ion dissipation(1.0 nA)for EP-GCN/EAMS-TiO_(2)coatedsteel.FE-SEM and EDX analyses revealed improved breakdown products and a durable inert nanolayered covering.Thenanocomposite exhibited excellent water resistance(water contact angle of 167°)and strong mechanical properties,withadhesive strength increasing to 18.3 MPa after 28 d in seawater.EP-GCN/EAMS-TiO_(2)shows potential as a coatingmaterial for the shipping industry. 展开更多
关键词 graphitic carbon nitride nanocomposites flame retardant coating corrosion functional materials
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Effects of Ultrasound-Assisted Alkaline Extraction on the Structural and Emulsifying Properties of Chickpea Protein Isolate
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作者 ZHANG Yixue YANG Qing +4 位作者 CHENG Teng ZHENG Ruihan MA Wuchao HE Xiangli LI Ke 《食品科学》 北大核心 2025年第19期236-247,共12页
This study aimed to investigate the effect of ultrasound-assisted alkaline extraction(UAE)(at 20 kHz and different powers of 0,200,300,400,500 and 600 W for 10 min)on the yield,structure and emulsifying properties of ... This study aimed to investigate the effect of ultrasound-assisted alkaline extraction(UAE)(at 20 kHz and different powers of 0,200,300,400,500 and 600 W for 10 min)on the yield,structure and emulsifying properties of chickpea protein isolate(CPI).Compared with the non-ultrasound group,ultrasound treatment at 400 W resulted in the largest increase in CPI yield,and both the particle size and turbidity decreased with increasing ultrasound power from 0 to 400 W.The scanning electron microscope results showed a uniform structural distribution of CPI.Moreover,itsα-helix content increased,β-sheet content decreased,and total sulfhydryl group content and endogenous fluorescence intensity rose,illustrating that UAE changed the secondary and tertiary structure of CPI.At 400 W,the solubility of the emulsion increased to 63.18%,and the best emulsifying properties were obtained;the emulsifying activity index(EAI)and emulsifying stability index(ESI)increased by 85.42%and 46.78%,respectively.Furthermore,the emulsion droplets formed were smaller and more uniform.In conclusion,proper UAE power conditions increased the extraction yield and protein content of CPI,and effectively improved its structure and emulsifying characteristics. 展开更多
关键词 CHICKPEA ULTRasOUND extraction yield protein structure functional properties
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Patterned Three-Dimensional Photonic Crystal Structures Based on Paper Substrates
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作者 WANG Ye-qi LI Xiu +1 位作者 HUANG Min LIU Yu 《印刷与数字媒体技术研究》 北大核心 2025年第4期62-69,共8页
In the printing industry,the common method of coloring relies on inks,which contains amounts of chemical agents,causing environment pollution.However,structural color achieves coloration through the refraction and dif... In the printing industry,the common method of coloring relies on inks,which contains amounts of chemical agents,causing environment pollution.However,structural color achieves coloration through the refraction and diffraction of light by periodic structure,offering eco-friendly and fade-resistant advantages,as well as colorful.In this study,screen printing was used to create patterned mask on paper substrates.Then,coated SiO_(2)microspheres on the mask to create structural color patterns with angle-dependent color characteristics.The patterns showed color changes from rose-red to orange to green by changing the viewing angle.By changing the color grayscale,the absorption of stray light by the substrate was enhanced,thereby the brightness and saturation of the structural color improved too.This method is simple,cost-effective,and environmentally friendly,and it has highly promising for the application in printing and anti-counterfeiting. 展开更多
关键词 Photonic crystal Structural color Screen printing SiO_(2)microsphere Environmental protection
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The use of an oxidized carbon nanotube film to control Zn deposition and eliminate dendrite formation in a Zn ion battery
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作者 LI Pin-xiang YI Zhe-han +3 位作者 WANG Ye-xing HE Chang LIANG Ji HOU Feng 《新型炭材料(中英文)》 北大核心 2025年第1期154-166,共13页
Aqueous zinc ion batteries are regarded as one of the most promising candidates for large-scale energy stor-age due to their high safety,cost-effectiveness,and environ-mental friendliness.However,uncontrolled zinc den... Aqueous zinc ion batteries are regarded as one of the most promising candidates for large-scale energy stor-age due to their high safety,cost-effectiveness,and environ-mental friendliness.However,uncontrolled zinc dendrite growth and side reactions of the zinc anode decrease the sta-bility of Zn batteries.We report the synthesis of an air-oxid-ized carbon nanotube(O-CNT)film by chemical vapor de-position followed by heat treatment in air which is used as a protective layer on the Zn foil to suppress zinc dendrite growth.The increase in the hydrophilicity of the O-CNT film caused by air oxidation facilitates zinc deposition between the film and the anode instead of deposition on the film surface.The porous structure of the O-CNT film homogenizes the Zn^(2+)ion flux and the electric field on the surface of the Zn foil,leading to the uniform deposition of Zn.As a result,a O-CNT@Zn symmetric cell has a much better cycling stability with a life of more than 3000 h at 1 mA cm^(−2) with a capacity of 1 mAh cm^(−2),and values of more than 2000 h and 1 mAh cm^(−2) at 5 mA cm^(−2).In addition,a O-CNT@Zn||Mn^(2+)inserted hydrated vanadium pentoxide(MnVOH)full cell has a better rate per-formance than a Zn||MnVOH cell,achieving a high discharge capacity of 194 mAh g^(−1) at a high current density of 8 A g^(−1).In a long-term cycling test,the O-CNT@Zn||MnVOH full cell has a capacity retention of 58.8%after 2000 cycles at a current density of 5 A·g^(−1). 展开更多
关键词 Carbon nanotubes Zn metal anodes Dendrite-free HYDROPHILIC Surface functionalization
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Molecular simulation study of the microstructures and properties of pyridinium ionic liquid[HPy][BF_(4)]mixed with acetonitrile
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作者 XU Jian-Qiang MA Zhao-Peng +2 位作者 CHENG Si LIU Zhi-Cong ZHU Guang-Lai 《原子与分子物理学报》 CAS 北大核心 2025年第4期27-32,共6页
The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this wo... The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this work.The following properties were determined:density,self-diffusion coefficient,excess molar volume,and radial distribution function.The results show that with an increase in the mole fraction of[HPy][BF_(4)],the self-diffusion coefficient decreases.Additionally,the excess molar volume initially decreases,reaches a minimum,and then increases.The rules of radial distribution functions(RDFs)of characteristic atoms are different.With increasing the mole fraction of[HPy][BF_(4)],the first peak of the RDFs of HA1-F decreases,while that of CT6-CT6 rises at first and then decreases.This indicates that the solvent molecules affect the polar and non-polar regions of[HPy][BF_(4)]differently. 展开更多
关键词 Pyridinium ionic liquids thermodynamic properties Molecular dynamics simulation Radial distribution functions
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A whole process damage constitutive model for layered sandstone under uniaxial compression based on Logistic function 被引量:1
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作者 LIU Dong-qiao GUO Yun-peng +1 位作者 LING Kai LI Jie-yu 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2411-2430,共20页
Bedding structural planes significantly influence the mechanical properties and stability of engineering rock masses.This study conducts uniaxial compression tests on layered sandstone with various bedding angles(0... Bedding structural planes significantly influence the mechanical properties and stability of engineering rock masses.This study conducts uniaxial compression tests on layered sandstone with various bedding angles(0°,15°,30°,45°,60°,75°and 90°)to explore the impact of bedding angle on the deformational mechanical response,failure mode,and damage evolution processes of rocks.It develops a damage model based on the Logistic equation derived from the modulus’s degradation considering the combined effect of the sandstone bedding dip angle and load.This model is employed to study the damage accumulation state and its evolution within the layered rock mass.This research also introduces a piecewise constitutive model that considers the initial compaction characteristics to simulate the whole deformation process of layered sandstone under uniaxial compression.The results revealed that as the bedding angle increases from 0°to 90°,the uniaxial compressive strength and elastic modulus of layered sandstone significantly decrease,slightly increase,and then decline again.The corresponding failure modes transition from splitting tensile failure to slipping shear failure and back to splitting tensile failure.As indicated by the modulus’s degradation,the damage characteristics can be categorized into four stages:initial no damage,damage initiation,damage acceleration,and damage deceleration termination.The theoretical damage model based on the Logistic equation effectively simulates and predicts the entire damage evolution process.Moreover,the theoretical constitutive model curves closely align with the actual stress−strain curves of layered sandstone under uniaxial compression.The introduced constitutive model is concise,with fewer parameters,a straightforward parameter determination process,and a clear physical interpretation.This study offers valuable insights into the theory of layered rock mechanics and holds implications for ensuring the safety of rock engineering. 展开更多
关键词 layered sandstone uniaxial compression damage evolution Logistic function constitutive model
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A series of iridium(Ⅲ)complexes with fluorophenyl isoquinoline ligand and low-efficiency roll-off properties:A density functional theory study
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作者 QIN Zhengkun PAN Zicong +2 位作者 TIAN Hui ZHANG Wanyi SONG Mingxing 《无机化学学报》 北大核心 2025年第6期1235-1244,共10页
We have examined the theoretical implications of combining two main and three auxiliary ligands to form several Ir(Ⅲ)complexes featuring a transition metal as their core atom to identify some appropriate organic ligh... We have examined the theoretical implications of combining two main and three auxiliary ligands to form several Ir(Ⅲ)complexes featuring a transition metal as their core atom to identify some appropriate organic lightemitting diode(OLED)materials.By utilizing electronic structure,frontier molecular orbitals,minimum single-line absorption,triplet excited states,and emission spectral data derived from the density functional theory,the usefulness of these Ir(Ⅲ)complexes,including(piq)_(2)Ir(acac),(piq)_(2)Ir(tmd),(piq)_(2)Ir(tpip),(fpiq)_(2)Ir(acac),(fpiq)_(2)Ir(tmd),and(fpiq)_(2)Ir(tpip),in OLEDs was examined,where piq=1-phenylisoquinoline,fpiq=1-(4-fluorophenyl)isoquinoline,acac=(3Z)-4-hydroxypent-3-en-2-one,tmd=(4Z)-5-hydroxy-2,2,6,6-tetramethylhept-4-en-3-one,and tpip=tetraphenylimido-diphosphonate.These complexes all have low-efficiency roll-off properties,especially(fpiq)_(2)Ir(tpip).Some researchers have successfully synthesized complexes extremely similar to(piq)_(2)Ir(acac)through the Suzuki-Miyaura coupling reaction. 展开更多
关键词 density functional theory organic light-emitting diodes luminescent materials Ir(Ⅲ)complexes
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rTMS Improves Cognitive Function and Brain Network Connectivity in Patients With Alzheimer’s Disease
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作者 XU Gui-Zhi LIU Lin +4 位作者 GUO Miao-Miao WANG Tian GAO Jiao-Jiao JI Yong WANG Pan 《生物化学与生物物理进展》 北大核心 2025年第8期2131-2145,共15页
Objective Repetitive transcranial magnetic stimulation(rTMS)has demonstrated efficacy in enhancing neurocognitive performance in Alzheimer’s disease(AD),but the neurobiological mechanisms linking synaptic pathology,n... Objective Repetitive transcranial magnetic stimulation(rTMS)has demonstrated efficacy in enhancing neurocognitive performance in Alzheimer’s disease(AD),but the neurobiological mechanisms linking synaptic pathology,neural oscillatory dynamics,and brain network reorganization remain unclear.This investigation seeks to systematically evaluate the therapeutic potential of rTMS as a non-invasive neuromodulatory intervention through a multimodal framework integrating clinical assessments,molecular profiling,and neurophysiological monitoring.Methods In this prospective double-blind trial,12 AD patients underwent a 14-day protocol of 20 Hz rTMS,with comprehensive multimodal assessments performed pre-and postintervention.Cognitive functioning was quantified using the mini-mental state examination(MMSE)and Montreal cognitive assessment(MOCA),while daily living capacities and neuropsychiatric profiles were respectively evaluated through the activities of daily living(ADL)scale and combined neuropsychiatric inventory(NPI)-Hamilton depression rating scale(HAMD).Peripheral blood biomarkers,specifically Aβ1-40 and phosphorylated tau(p-tau181),were analyzed to investigate the effects of rTMS on molecular metabolism.Spectral power analysis was employed to investigate rTMS-induced modulations of neural rhythms in AD patients,while brain network analyses incorporating topological properties were conducted to examine stimulus-driven network reorganization.Furthermore,systematic assessment of correlations between cognitive scale scores,blood biomarkers,and network characteristics was performed to elucidate cross-modal therapeutic associations.Results Clinically,MMSE and MOCA scores improved significantly(P<0.05).Biomarker showed that Aβ1-40 level increased(P<0.05),contrasting with p-tau181 reduction.Moreover,the levels of Aβ1-40 were positively correlated with MMSE and MOCA scores.Post-intervention analyses revealed significant modulations in oscillatory power,characterized by pronounced reductions in delta(P<0.05)and theta bands(P<0.05),while concurrent enhancements were observed in alpha,beta,and gamma band activities(all P<0.05).Network analysis revealed frequency-specific reorganization:clustering coefficients were significantly decreased in delta,theta,and alpha bands(P<0.05),while global efficiency improvement was exclusively detected in the delta band(P<0.05).The alpha band demonstrated concurrent increases in average nodal degree(P<0.05)and characteristic path length reduction(P<0.05).Further research findings indicate that the changes in the clinical scale HAMD scores before and after rTMS stimulation are negatively correlated with the changes in the blood biomarkers Aβ1-40 and p-tau181.Additionally,the changes in the clinical scales MMSE and MoCA scores were negatively correlated with the changes in the node degree of the alpha frequency band and negatively correlated with the clustering coefficient of the delta frequency band.However,the changes in MMSE scores are positively correlated with the changes in global efficiency of both the delta and alpha frequency bands.Conclusion 20 Hz rTMS targeting dorsolateral prefrontal cortex(DLPFC)significantly improves cognitive function and enhances the metabolic clearance ofβ-amyloid and tau proteins in AD patients.This neurotherapeutic effect is mechanistically associated with rTMS-mediated frequency-selective neuromodulation,which enhances the connectivity of oscillatory networks through improved neuronal synchronization and optimized topological organization of functional brain networks.These findings not only support the efficacy of rTMS as an adjunctive therapy for AD but also underscore the importance of employing multiple assessment methods—including clinical scales,blood biomarkers,and EEG——in understanding and monitoring the progression of AD.This research provides a significant theoretical foundation and empirical evidence for further exploration of rTMS applications in AD treatment. 展开更多
关键词 transcranial magnetic stimulation Alzheimer’s disease power spectral density ELECTROENCEPHALOGRAM brain functional network
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Research on the protection mechanism of methane explosion in underground space by flexible construction
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作者 Xianqi Duan Yulong Duan +3 位作者 Zishuang Zhang Jun Long Yaqiao Yang Rui Lang 《Defence Technology(防务技术)》 2025年第4期169-183,共15页
Urban growth has promoted the use of underground spaces,where explosion accidents can be catastrophic.In this study,we investigated the effect of placing flexible construction in front of rigid obstacles on methane ex... Urban growth has promoted the use of underground spaces,where explosion accidents can be catastrophic.In this study,we investigated the effect of placing flexible construction in front of rigid obstacles on methane explosion protection by using an experimental platform and adjusting the blockage rate and spacing of the obstacles.It aims to reduce the risk of gas explosions in urban underground spaces.The results of the study show that the flame propagation peak speed and peak overpressure are reduced with the decrease in the blocking rate of the flexible obstacle when the blocking rate of the flexible obstacle is less than or equal to the blocking rate of the rigid obstacle,with the decrease in the spacing,the better the protection effect of the methane explosion.When the blockage rate of the flexible obstacle is greater than the blockage rate of the rigid obstacle and spacing is less than the height of the flexible obstacle,rigid and flexible obstacles are connected as a whole,increasing the strength of the explosion.This study can provide a theoretical basis and scientific guidance for optimizing rigid and flexible object hybrid layouts and methane explosion protection technology in urban underground spaces. 展开更多
关键词 Explosion protection Flexible construction Urban underground space Methane explosions
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Photothermal self-healing polyurethane coating based on hollow nanofillers in seawater
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作者 KANG Qian-qian MAO Zhi-peng +3 位作者 PENG Li-ming MYRONYUK Oleksiy LI Wei-hua WANG Wei 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第10期3447-3462,共16页
Herein,a novel composite coating with excellent self-healing and corrosion resistance activated byphotothermal responsive hollow core-shell nanofillers was developed.A photothermal nanofiller(Co_(9)S_(8)@Bi_(2)S_(3))w... Herein,a novel composite coating with excellent self-healing and corrosion resistance activated byphotothermal responsive hollow core-shell nanofillers was developed.A photothermal nanofiller(Co_(9)S_(8)@Bi_(2)S_(3))with ahollow core-shell structure was synthesized and then added to polyurethane(PU)to prepare PU-Co_(9)S_(8)@Bi_(2)S_(3)compositecoating.Applying 808 nm near-infrared irradiation induces a photothermal effect in Co_(9)S_(8)@Bi_(2)S_(3),which subsequentlyinitiates the reconstruction of reversible hydrogen bonds,facilitating the self-healing of coating scratches.The excellentphotothermal self-healing performance of PU-Co_(9)S_(8)@Bi_(2)S_(3)coating was demonstrated by scratch tests and moleculardynamics simulations.The electrochemical impedance spectroscopy test results showed that the PU-Co_(9)S_(8)@Bi_(2)S_(3)coating has good self-healing and anti-corrosion properties.The low-frequency impedance modulus of the coating afterthree self-healing sessions was still close to 109Ω·cm^(2)after 30 d of immersion in seawater.This study provides a newstrategy for developing multi-cycle self-healing coatings triggered by photothermal effects. 展开更多
关键词 polyurethane coating photothermal effect SELF-HEALING corrosion protection
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Variable reward function-driven strategies for impulsive orbital attack-defense games under multiple constraints and victory conditions
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作者 Liran Zhao Sihan Xu +1 位作者 Qinbo Sun Zhaohui Dang 《Defence Technology(防务技术)》 2025年第9期159-183,共25页
This paper investigates impulsive orbital attack-defense(AD)games under multiple constraints and victory conditions,involving three spacecraft:attacker,target,and defender.In the AD scenario,the attacker aims to breac... This paper investigates impulsive orbital attack-defense(AD)games under multiple constraints and victory conditions,involving three spacecraft:attacker,target,and defender.In the AD scenario,the attacker aims to breach the defender's interception to rendezvous with the target,while the defender seeks to protect the target by blocking or actively pursuing the attacker.Four different maneuvering constraints and five potential game outcomes are incorporated to more accurately model AD game problems and increase complexity,thereby reducing the effectiveness of traditional methods such as differential games and game-tree searches.To address these challenges,this study proposes a multiagent deep reinforcement learning solution with variable reward functions.Two attack strategies,Direct attack(DA)and Bypass attack(BA),are developed for the attacker,each focusing on different mission priorities.Similarly,two defense strategies,Direct interdiction(DI)and Collinear interdiction(CI),are designed for the defender,each optimizing specific defensive actions through tailored reward functions.Each reward function incorporates both process rewards(e.g.,distance and angle)and outcome rewards,derived from physical principles and validated via geometric analysis.Extensive simulations of four strategy confrontations demonstrate average defensive success rates of 75%for DI vs.DA,40%for DI vs.BA,80%for CI vs.DA,and 70%for CI vs.BA.Results indicate that CI outperforms DI for defenders,while BA outperforms DA for attackers.Moreover,defenders achieve their objectives more effectively under identical maneuvering capabilities.Trajectory evolution analyses further illustrate the effectiveness of the proposed variable reward function-driven strategies.These strategies and analyses offer valuable guidance for practical orbital defense scenarios and lay a foundation for future multi-agent game research. 展开更多
关键词 Orbital attack-defense game Impulsive maneuver Multi-agent deep reinforcement learning Reward function design
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A diagnosis method based on graph neural networks embedded with multirelationships of intrinsic mode functions for multiple mechanical faults
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作者 Bin Wang Manyi Wang +3 位作者 Yadong Xu Liangkuan Wang Shiyu Chen Xuanshi Chen 《Defence Technology(防务技术)》 2025年第8期364-373,共10页
Fault diagnosis occupies a pivotal position within the domain of machine and equipment management.Existing methods,however,often exhibit limitations in their scope of application,typically focusing on specific types o... Fault diagnosis occupies a pivotal position within the domain of machine and equipment management.Existing methods,however,often exhibit limitations in their scope of application,typically focusing on specific types of signals or faults in individual mechanical components while being constrained by data types and inherent characteristics.To address the limitations of existing methods,we propose a fault diagnosis method based on graph neural networks(GNNs)embedded with multirelationships of intrinsic mode functions(MIMF).The approach introduces a novel graph topological structure constructed from the features of intrinsic mode functions(IMFs)of monitored signals and their multirelationships.Additionally,a graph-level based fault diagnosis network model is designed to enhance feature learning capabilities for graph samples and enable flexible application across diverse signal sources and devices.Experimental validation with datasets including independent vibration signals for gear fault detection,mixed vibration signals for concurrent gear and bearing faults,and pressure signals for hydraulic cylinder leakage characterization demonstrates the model's adaptability and superior diagnostic accuracy across various types of signals and mechanical systems. 展开更多
关键词 Fault diagnosis Graph neural networks Graph topological structure Intrinsic mode functions Feature learning
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Significantly enhanced photoelectrochemical cathodic protection performance and preventing biofouling dual functional Cu_(2)ZnSnS_(4)/TiO_(2)nanotube composite material
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作者 XUE Jun-jie QIN Ying-nan +3 位作者 YAN Ke-xin SAND Wolfgang GAO Hong-tao WANG Ning 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第10期3583-3595,共13页
A new type of photoelectrochemical cathodic protection technology(a combination of seawater corrosion and biological fouling resistance)is being actively researched to alleviate the serious corrosion of marine metal m... A new type of photoelectrochemical cathodic protection technology(a combination of seawater corrosion and biological fouling resistance)is being actively researched to alleviate the serious corrosion of marine metal materials.At present,there is almost no research on anti-corrosion and anti-fouling dual functional materials.In this paper,Cu_(2)ZnSnS_(4)is attached to the surface of TiO,nanotubes through a one-step hydrothermal method for modification.The results indicate that when the hydrothermal reaction time is 24 h,Cu_(2)ZnSnS_(4)/TiO_(2)nanocomposite material exhibits excellent performance in coupling with the protected 304 SS,with its open circuit potential shifts negatively to-1.04 V.This material improves the separation efficiency of photogenerated electrons and effectively improves the photochemical cathodic protection of 304 stainless steel.The high removal rate of Staphylococcus aureus(up to 93%)of the as-prepared samples also proved that it has the effect of the anti-biological fouling. 展开更多
关键词 photoelectrochemical cathodic protection ANTI-CORROSION Cu_(2)ZnSnS_(4) anti-biofouling Staphylococcus aureu
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Construction and biological function of Toxoplasma gondii rop41 gene knockout strain
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作者 WU Kaijuan XIE Jing +5 位作者 LIU Xiaohua YANG Dongqian WANG Yixiao ZHAO Wanchen SHANG Xiaomin JIANG Liping 《中南大学学报(医学版)》 CAS CSCD 北大核心 2024年第8期1200-1209,共10页
Objective:Toxoplasmosis is a zoonotic parasitic disease caused by Toxoplasma gondii(T.gondii),which can lead to complications such as encephalitis and ocular toxoplasmosis.The disease becomes more severe when the host... Objective:Toxoplasmosis is a zoonotic parasitic disease caused by Toxoplasma gondii(T.gondii),which can lead to complications such as encephalitis and ocular toxoplasmosis.The disease becomes more severe when the host’s immune system is compromised.Rhoptry proteins are major virulence factors that enable T.gondii to invade host cells.This study aims to construct a T.gondii rhoptry protein 41(rop41/ROP41)gene knockout strain and preliminarily investigate the biological function of rop41.Methods:Using CRISPR/Cas9 technology,a specific single-guide RNA(sgRNA)for the target gene was designed and linked to a recombinant plasmid.Homologous fragments were fused with a pyrimethamine resistance gene for selection purposes.The recombinant plasmid and the homologous fragments were electroporated into T.gondii,and PCR identification was performed after drug selection and monoclonal screening.Plaque assays were used to comprehensively assess whether rop41 affected the growth and proliferation of T.gondii in host cells.Invasion and proliferation assays were conducted to evaluate the invasion ability of the knockout strain into host cells and its intracellular proliferation capacity.The STRING database was utilized to construct a protein-protein interaction(PPI)network,and functional enrichment analysis was performed to predict the signaling pathways in which ROP41 might be involved.Results:The T.gondii rop41 gene knockout strain(RHΔku80Δrop41)was successfully constructed and stably inherited.Plaque assays showed that compared with the parental strain,the number of plaques formed by the rop41 gene knockout strain did not significantly decrease,but the reduction in plaque size was statistically significant(P<0.05).After the rop41 gene was knocked out,the invasion ability of T.gondii was reduced,but there was no statistically significant difference in its proliferation ability(P>0.05).The PPI network revealed that ROP41 was associated with other protein kinases and autophagy related proteins.Enrichment analysis indicated that proteins interacting with ROP41 may be involved in signal transduction,biosynthesis,metabolism,and autophagy-related pathways and could be components of various kinase complexes and phagocytic vesicles.Conclusion:The T.gondii RHΔku80Δrop41 strain has been successfully constructed.ROP41 primarily affects the ability of T.gondii to invade host cells and may play a role in signal transduction and autophagy-related pathways between T.gondii and the host. 展开更多
关键词 toxoplasma gondii rhoptry protein 41 gene knockout functional enrichment analysis
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An isogeometric approach for vibration characteristics analysis of functionally graded triply periodic minimal sandwich curved-doubly shell integrated with magneto-electro surface layers subjected to lowvelocity impact load
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作者 Le Hoai Pham Hoang Tu +1 位作者 Van Ke Tran Nguyen Thi Hue 《Defence Technology(防务技术)》 2025年第8期101-125,共25页
In this paper,the isogeometric analysis(IGA)method is employed to analyze the oscillation characteristics of functionally graded triply periodic minimal surface(FG-TPMS)curved-doubly shells integrated with magneto-ele... In this paper,the isogeometric analysis(IGA)method is employed to analyze the oscillation characteristics of functionally graded triply periodic minimal surface(FG-TPMS)curved-doubly shells integrated with magneto-electric surface layers(referred to as"FG-TPMS-MEE curved-doubly shells")subjected to low-velocity impact loads.This study presents low-velocity impact load model based on a single springmass(S-M)approach.The FG-TPMS-MEE curved-doubly shells are covered with two magneto-electric surface layers,while the core layer consists of three types:I-graph and Wrapped Package-graph(IWP),Gyroid(G),and Primitive(P),with various graded functions.These types are notable for their exceptional stiffness-to-weight ratios,enabling a wide range of potential applications.The Maxwell equations and electromagnetic boundary conditions are applied to compute the change in electric potentials and magnetic potentials.The equilibrium equations of the shell are derived from a refined higher-order shear deformation theory(HSDT),and the transient responses of the FG-TPMS-MEE curveddoubly shells are subsequently determined using Newmark's direct integration method.These results have applications in structural vibration control and the analysis of structures subjected to impact or explosive loads.Furthermore,this study provides a theoretical prediction of the low-velocity impact load and magneto-electric-elastic effects on the free vibration and transient response of FG-TPMS-MEE curved-doubly shells. 展开更多
关键词 IGA approach Free vibration and transient response Magneto-electro-elastic curved-doubly shell Low-velocity impact load functionally graded triply periodic minimal
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Second-Order Side-Channel Attacks on Kyber: Targeting the Masked Hash Function
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作者 WANG Ya-Qi HUANG Fan +1 位作者 DUAN Xiao-Lin HU Hong-Gang 《密码学报(中英文)》 CSCD 北大核心 2024年第6期1415-1436,共22页
Recently,several PC oracle based side-channel attacks have been proposed against Kyber.However,most of them focus on unprotected implementations and masking is considered as a counter-measure.In this study,we extend P... Recently,several PC oracle based side-channel attacks have been proposed against Kyber.However,most of them focus on unprotected implementations and masking is considered as a counter-measure.In this study,we extend PC oracle based side-channel attacks to the second-order scenario and successfully conduct key-recovery attacks on the first-order masked Kyber.Firstly,we analyze the potential joint information leakage.Inspired by the binary PC oracle based attack proposed by Qin et al.at Asiacrypt 2021,we identify the 1-bit leakage scenario in the masked Keccak implementation.Moreover,we modify the ciphertexts construction described by Tanaka et al.at CHES 2023,extending the leakage scenario from 1-bit to 32-bit.With the assistance of TVLA,we validate these leakages through experiments.Secondly,for these two scenarios,we construct a binary PC oracle based on t-test and a multiple-valued PC oracle based on neural networks.Furthermore,we conduct practical side-channel attacks on masked Kyber by utilizing our oracles,with the implementation running on an ARM Cortex-M4 microcontroller.The demonstrated attacks require a minimum of 15788 and 648 traces to fully recover the key of Kyber768 in the 1-bit leakage scenario and the 32-bit leakage scenario,respectively.Our analysis may also be extended to attack other post-quantum schemes that use the same masked hash function.Finally,we apply the shuffling strategy to the first-order masked imple-mentation of the Kyber and perform leakage tests.Experimental results show that the combination strategy of shuffling and masking can effectively resist our proposed attacks. 展开更多
关键词 side-channel attack plaintext-checking oracle post-quantum cryptography masked Kyber masked hash function
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Exploring the effects of angle of incidence on stabbing resistance in advanced protective textiles:Novel experimental framework and analysis
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作者 Mulat Alubel Abtew François Boussu Irina Cristian 《Defence Technology(防务技术)》 2025年第2期67-82,共16页
Despite numerous research investigations to understand the influences of various structural parameters,to the authors'knowledge,no research has been the effect of different angles of incidence on stab response and... Despite numerous research investigations to understand the influences of various structural parameters,to the authors'knowledge,no research has been the effect of different angles of incidence on stab response and performance of different types of protective textiles.Three distinct structures of 3D woven textiles and 2D plain weave fabric made with similar high-performance fiber and areal density were designed and manufactured to be tested.Two samples,one composed of a single and the other of 4-panel layers,from each fabric type structure,were prepared,and tested against stabbing at[0○],[22.5○],and[45○]angle of incidence.A new stabbing experimental setup that entertained testing of the specimens at various angles of incidence was engineered and utilized.The stabbing bench is also equipped with magnetic sensors and a UK Home Office Scientific Development Branch(HOSDB)/P1/B sharpness engineered knives to measure the impact velocity and exerted impact energy respectively.A silicon compound was utilized to imprint the Back Face Signature(BFS)on the backing material after every specimen test.Each silicon print was then scanned,digitized,and precisely measured to evaluate the stab response and performance of the specimen based on different performance variables,including Depth of Trauma(DOT),Depth of Penetration(DOP),and Length of Penetration(LOP).Besides,the post-impact surface failure modes of the fabrics were also measured using Image software and analyzed at the microscale level.The results show stab angle of incidence greatly influences the stab response and performance of protective textiles.The outcome of the study could provide not only valuable insights into understanding the stab response and capabilities of protective textiles under different angle of incidence,but also provide valuable information for protective textile manufacturer,armor developer and stab testing and standardizing organizations to consider the angle of incidence while developing,testing,optimizing,and using protective textiles in various applications. 展开更多
关键词 2D/3D woven fabrics Impact protective fabric Drop tower perforation test Stab resistance testing protocol Angle of incidence Multi-layer panels Soft body armor Impact surface damage
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