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Elastoplastical analysis on cylinder of different moduli in tension and compression
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作者 WANG Wei-ming ZHANG Xiao-yan YANG Zhao WANG Qing-biao 《Journal of Coal Science & Engineering(China)》 2009年第1期66-71,共6页
The constitutive equation was deduced. The results were obtained from theelastic and elastoplastical analysis of the cylinder sample applied with different ratios ofload on both the inner and outer sides and different... The constitutive equation was deduced. The results were obtained from theelastic and elastoplastical analysis of the cylinder sample applied with different ratios ofload on both the inner and outer sides and different moduli ratio. The factors affecting thedevelopment of the plastic field of the cylinder with finite radius were shown. The resultsshow that the different moduli ratio is the most important factor in the development of theplastic zone. The slight fluctuation of the ratio will bring multiplied increment of the displacement, which may result in the final destruction of the engineering material. 展开更多
关键词 CYLINDER different moduli plastic zone elastoplastical analysis
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Effects of Strain Rate and Deformation Temperature on Microstructures and Hardness in Plastically Deformed Pure Aluminum 被引量:12
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作者 F. Huang N.R. Taot K. Lu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2011年第1期1-7,共7页
The microstructures and hardness of pure Al samples subjected to plastic deformation with different tem- peratures and strain rates were investigated. The results showed that the strain-induced grain refinement is sig... The microstructures and hardness of pure Al samples subjected to plastic deformation with different tem- peratures and strain rates were investigated. The results showed that the strain-induced grain refinement is significantly benefited by increasing strain rate and reducing deformation temperature. The saturated size of refined subgrains in Al can be as small as about 240 nm in cryogenic dynamic plastic deformation (DPD). Grain boundaries of the DPD Al samples are low-angle boundaries due to suppression of dynamic recovery during deformation. Agreement of the measured hardness with the empirical Hall-Petch relation extrapolated from the coarse-grained Al implies that the low-angle boundaries can contribute to strengthening as effective as the conventional grain boundaries. 展开更多
关键词 Dynamic plastic deformation MICROSTRUCTURE HARDNESS Strain rate TEMPERATURE
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Corrosion behavior of severely plastically deformed Mg and Mg alloys 被引量:13
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作者 Ahmad Bahmani Mehrab Lotfpour +1 位作者 Milad Taghizadeh Woo-Jin Kim 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2022年第10期2607-2648,共42页
Magnesium(Mg)alloys have several advantages,such as low density,high specific strength and biocompatibility.However,they also suffer weak points,such as high corrosion,low formability and easy ignition,which makes the... Magnesium(Mg)alloys have several advantages,such as low density,high specific strength and biocompatibility.However,they also suffer weak points,such as high corrosion,low formability and easy ignition,which makes their applications limited.Many studies have been conducted to overcome these disadvantages and further improve the advantages of Mg alloys.Severe plastic deformation(SPD)is one of the most important techniques and has great effects on the microstructure refinement of Mg alloys and improvements in their strength and formability.Several researchers have studied the corrosion behavior of SPD-processed Mg alloys in recent decades.However,these studies have reported some controversial effects of SPD on the corrosion of Mg alloys,which makes the research roadmap ambiguous.Therefore,it is important to review the literature related to the corrosion properties of Mg alloys prepared by SPD and understand the mechanisms controlling their corrosion behavior.Effective grain refinement by SPD improves the corrosion properties of pure Mg and Mg alloys,but control of the processing conditions is a key factor for achieving this goal because texture,dislocation density,size and morphology of secondary phase also importantly affects the corrosion properties of Mg alloys.Reduced grain size in the fine grain-size range can decrease the corrosion rate due to the increased barrier effect of grain boundaries against corrosion and the formation of a stable passivation layer on the surface of fine grains.Basal texture reduces the corrosion rate because basal planes with the highest atomic planar density are more corrosion resistant than other planes.Increased dislocation density after SPD deteriorates the corrosion resistance of the interior grains and thus proper annealing after SPD is important.The fine and uniform distribution of secondary phase particles during SPD is important to minimize the micro-galvanic corrosion effect and retain small grains during annealing treatment for removing dislocations. 展开更多
关键词 Magnesium alloys CORROSION Severe plastic deformation Grain size Secondary phase Dislocation density
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Indentation of elastically soft and plastically compressible solids 被引量:4
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作者 A.Needleman V.Tvergaard E.Van der Giessen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2015年第4期473-480,共8页
The effect of soft elasticity, i.e., a relatively small value of the ratio of Young's modulus to yield strength and plastic compressibility on the indentation of isotropically hardening elastic-viscoplastic solids is... The effect of soft elasticity, i.e., a relatively small value of the ratio of Young's modulus to yield strength and plastic compressibility on the indentation of isotropically hardening elastic-viscoplastic solids is investigated. Calcu- lations are carried out for indentation of a perfectly sticking rigid sharp indenter into a cylinder modeling indentation of a half space. The material is characterized by a finite strain elastic-viscoplastic constitutive relation that allows for plas- tic as well as elastic compressibility. Both soft elasticity and plastic compressibility significantly reduce the ratio of nomi- nal indentation hardness to yield strength. A linear relation is found between the nominal indentation hardness and the log- arithm of the ratio of Young's modulus to yield strength, but with a different coefficient than reported in previous studies. The nominal indentation hardness decreases rapidly for small deviations from plastic incompressibility and then decreases rather slowly for values of the plastic Poisson's ratio less than 0.25. For both soft elasticity and plastic compressibility, the main reason for the lower values of indentation hardness is related to the reduction in the hydrostatic stress level in the material below the indenter. 展开更多
关键词 PLASTICITY COMPRESSIBILITY INDENTATION Finite element analysis
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Deformation of plastically compressible hardening-softening-hardening solids 被引量:2
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作者 A. Needleman S. B. Hutchens +1 位作者 N. Mohan J. R. Greer 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第4期1115-1124,共10页
Motivated by a model of the response of vertically aligned carbon nanotube (VACNT) pillars in uniaxial compression, we consider the deformation of a class of compressible elastic-viscoplastic solids with a hardening... Motivated by a model of the response of vertically aligned carbon nanotube (VACNT) pillars in uniaxial compression, we consider the deformation of a class of compressible elastic-viscoplastic solids with a hardeningsoftening-hardening variation of flow strength with plastic strain. In previous work (Hutchens et al. 2011) a constitutive relation was presented and used to model the response of VACNT pillars in axisymmetric compression. Subsequently, it was found that due to a programming error the constitutive relation presented in the paper (Hutchens et al. 2011) was not the one actually implemented. In particular, the plastic flow rule actually used did not satisfy plastic normality. Here, we present the constitutive formulation actually implemented in the previous work (Hutchens et al. 2011). Dynamic, finite deformation, finite element calculations are carried out for uniaxial compression, uniaxial tension and for indentation of a "half-space" by a conical indenter tip. A sequential buckling-like deformation mode is found in compression when there is plastic non-normality and hardening- softening-hardening. The same material characterization gives rise to a Lfiders band-like deformation mode in ten- sion. When there is a deformation mode with a sharp front along mesh boundaries, the overall stress-strain response contains high frequency oscillations that are a mesh artifact. The responses of non-softening solids are also analyzed and their overall stress-strain behavior and deformation modes are compared with those of hardening-softening- hardening solids. We find that indentation with a sharp indenter tip gives a qualitatively equivalent response for hardening and hardening-softening-hardening solids. 展开更多
关键词 PLASTICITY Localization Indentation . Finite Element Analysis
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Finite deformation analysis of crack tip fields in plastically compressible hardening–softening–hardening solids 被引量:1
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作者 D.Khan S.Singh A.Needleman 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2017年第1期148-158,共11页
Crack tip fields are calculated under plane strain small scale yielding conditions. The material is characterized by a finite strain elastic-viscoplastic constitutive relation with various hardening-softening-hardenin... Crack tip fields are calculated under plane strain small scale yielding conditions. The material is characterized by a finite strain elastic-viscoplastic constitutive relation with various hardening-softening-hardening hardness functions. Both plastically compressible and plastically incompressible solids are considered. Displacements corresponding to the isotropic linear elastic mode I crack field are prescribed on a remote boundary. The initial crack is taken to be a semi-circular notch and symmetry about the crack plane is imposed. Plastic compressibility is found to give an increased crack opening displacement for a given value of the applied loading. The plastic zone size and shape are found to depend on the plastic compressibility, but not much on whether material softening occurs near the crack tip. On the other hand, the near crack tip stress and deformation fields depend sensitively on whether or not material softening occurs. The combination of plastic compressibility and softening (or softening-hardening) has a particularly strong effect on the near crack tip stress and deformation fields. 展开更多
关键词 PLASTICITY Crack tip fields FRACTURE Compressible solids Material softening
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Corrosion properties of plastically deformed AZ80 magnesium alloy 被引量:1
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作者 张治民 徐宏妍 李保成 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第B07期697-702,共6页
AZ80 magnesium alloys were deformed at 200,250,300,350 and 400℃ with different deformation degree of 50%,75%, 83%,87%and 90%,respectively.The corrosion properties of different deformed AZ80 samples were studied by ga... AZ80 magnesium alloys were deformed at 200,250,300,350 and 400℃ with different deformation degree of 50%,75%, 83%,87%and 90%,respectively.The corrosion properties of different deformed AZ80 samples were studied by galvanic test in 3.5%NaCl solution.The results show that plastic deformation could improve the corrosion resistance of AZ80 alloy;and the corrosion rate of AZ80 deformed at 250℃ with the deformation degree of 83%was the lowest,which was 33%of the as-cast AZ80 alloy.Further studies of the microstructure show that the refined grain size and continuously distribution ofβphase around the grain boundary did have a positive effect on the improvement of corrosion resistance of AZ80 alloys.For AZ80 alloys,the smaller the grain size is,the more homogeneous the structure is,and the better the corrosion resistance is. 展开更多
关键词 corrosion property plastic deformation AZ80 magnesium alloy
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Metabolic reprogramming of astrocytes:Emerging roles of lactate 被引量:1
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作者 Zeyu Liu Yijian Guo +2 位作者 Ying Zhang Yulei Gao Bin Ning 《Neural Regeneration Research》 2026年第2期421-432,共12页
Lactate serves as a key energy metabolite in the central nervous system,facilitating essential brain functions,including energy supply,signaling,and epigenetic modulation.Moreover,it links epigenetic modifications wit... Lactate serves as a key energy metabolite in the central nervous system,facilitating essential brain functions,including energy supply,signaling,and epigenetic modulation.Moreover,it links epigenetic modifications with metabolic reprogramming.Nonetheless,the specific mechanisms and roles of this connection in astrocytes remain unclear.Therefore,this review aims to explore the role and specific mechanisms of lactate in the metabolic reprogramming of astrocytes in the central nervous system.The close relationship between epigenetic modifications and metabolic reprogramming was discussed.Therapeutic strategies for targeting metabolic reprogramming in astrocytes in the central nervous system were also outlined to guide future research in central nervous system diseases.In the nervous system,lactate plays an essential role.However,its mechanism of action as a bridge between metabolic reprogramming and epigenetic modifications in the nervous system requires future investigation.The involvement of lactate in epigenetic modifications is currently a hot research topic,especially in lactylation modification,a key determinant in this process.Lactate also indirectly regulates various epigenetic modifications,such as N6-methyladenosine,acetylation,ubiquitination,and phosphorylation modifications,which are closely linked to several neurological disorders.In addition,exploring the clinical applications and potential therapeutic strategies of lactic acid provides new insights for future neurological disease treatments. 展开更多
关键词 ASTROCYTE epigenetic modifications inflammation LACTATE lactylation METABOLIC PLASTICITY regeneration treatment
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Genesis of pink diamonds in lamproite and low-Ti-type kimberlite pipes on craton margins
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作者 GROVES DI ZHANG Liang +1 位作者 CHEN ZuYan BAI Feng 《岩石学报》 北大核心 2026年第2期383-392,共10页
Diamonds were formed in the mantle lithosphere,mostly at depths of 150~200km in the centres of Precambrian cratons,the buoyant ancient cores of continents.From there they were normally transported into the upper crust... Diamonds were formed in the mantle lithosphere,mostly at depths of 150~200km in the centres of Precambrian cratons,the buoyant ancient cores of continents.From there they were normally transported into the upper crust in kimberlite pipes whose diamonds are largely colourless and light yellow related to trace element N(Ia type),although brown,green,and more rarely blue-coloured diamonds are related to lattice defect and trace amounts of H,more rarely B and Ni.Pink diamonds are extremely rare in the approximately 90 diamondiferous pipes mined globally.Although small quantities have been discovered elsewhere,about 90%have been mined from the ca.1.3Ga Argyle diamond pipe in Western Australia,with the Arkhangelskaya diamond pipe in Russia the only other significant source.The pink colour at both Argyle and Arkhangelskaya is unrelated to trace elements and instead results from absorption of light from nanoscale(550nm)defects related to shear stress and plastic deformation.Macroscopically,defects are shown by glide planes,lamellae,and grain lines imposed on the originally colourless diamonds derived from their mantle source.The key question is why these defects were uniquely acquired in diamonds in the Argyle and Arkhangelskaya pipes.Unlike most diamondiferous pipes,Argyle is a rare diamondiferous volatile-rich lamproite pipe that was emplaced into the multiply deformed and rifted NNE-trending Halls Creek Orogen on the margin of the Kimberley Craton.Similarly,Arkhangelskaya in the Devonian Lomonosov kimberlite cluster is a volatile-rich low-Ti type kimberlite,a close relative to lamproite,that was emplaced into the multiply deformed Lapland-Kola Orogen on the rifted margin of the Kola Craton.These craton margins are underlain by subduction-induced volatile-enriched metasomatized mantle lithosphere in contrast to the more primeval mantle under craton centres.It is thus likely that shear stresses were exacerbated at Argyle and Arkangelskaya by rapid vertical emplacement of the anomalous volatile-enriched magmas at supercritical pressures and temperatures,that induced catastrophic phase separation of these volatiles and'mini seismic events'during rapid pressure drops during ascent from 200km depth to the surface.Such a mechanism is consistent with the presence of strongly resorbed and plastically deformed small brown industrial diamonds in the Argyle pipe.From a China perspective,it is potentially important that at 1.3Ga the alkaline Argyle pipe in northern Australia is placed adjacent to the North China Craton(NCC),with numerous world-class mineral deposits including the giant ca.1.4~1.2Ga alkaline Bayan Obo REE system on its margin.However,it is the southeastern margin of the Yangtze Craton and the Jiangnan Orogen with their lamproite pipes derived from metasomatized mantle lithosphere that present the most prospective regions for pink diamond occurrences. 展开更多
关键词 Pink diamond Plastic deformation LAMPROITE Low-Ti-type kimberlite Craton margin
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Evaluation of Low-Damping Properties Induced by Plastic Deformation and Heat Treatment in Co-Ni-Cr-Mo-Based Alloy
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作者 Wang Hao Tong Haotian +2 位作者 Tadashi Fujieda Takemi Chiba Akihiko Chiba 《稀有金属材料与工程》 北大核心 2026年第3期573-580,共8页
The strength and damping properties of Co-Ni-Cr-Mo-based alloys with 0.5wt%Nb addition after various plastic deformation and heat treatment processes were investigated.Through Vickers hardness tests,free resonance You... The strength and damping properties of Co-Ni-Cr-Mo-based alloys with 0.5wt%Nb addition after various plastic deformation and heat treatment processes were investigated.Through Vickers hardness tests,free resonance Young's modulus measurements,and microstructure analysis,the effects of dislocation density,vacancy formation,and recrystallization on the alloy performance were clarified.Results indicate that increasing the rolling reduction enhances damping property due to higher dislocation density,whereas aging below the recrystallization temperature reduces damping property via dislocation pinning by the Suzuki effect.Recrystallization heat treatment restores the original structure and damping level.This alloy possesses tensile strength of approximately 1500 MPa and logarithmic decrement valueδ^(-1) in the range of 2×10^(-4)–3×10^(-4),demonstrating superior mechanical properties compared with the Ti-based alloys,which makes it an excellent candidate material for ultrasonic tools and medical applications. 展开更多
关键词 Co-Ni-Cr-Mo-based alloy low-damping properties Suzuki effect plastic deformation
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Hippocampal damage through foreign body placement in organotypic cultures leads to plastic responses in newly born granule cells
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作者 Tassilo Jungenitz Lukas Frey +2 位作者 Sophia Kirscht Stephan W.Schwarzacher Angélica Zepeda 《Neural Regeneration Research》 2026年第3期1142-1150,共9页
The dentate gyrus of the hippocampus is a plastic structure that displays modifications at different levels in response to positive stimuli as well as to negative conditions such as brain damage.The latter involves gl... The dentate gyrus of the hippocampus is a plastic structure that displays modifications at different levels in response to positive stimuli as well as to negative conditions such as brain damage.The latter involves global alterations,making understanding plastic responses triggered by local damage difficult.One key feature of the dentate gyrus is that it contains a well-defined neurogenic niche,the subgranular zone,and beyond neurogenesis,newly born granule cells may maintain a“young”phenotype throughout life,adding to the plastic nature of the structure.Here,we present a novel experimental model of local brain damage in organotypic entorhino-hippocampal cultures that results in the activation of adjacent newly born granule cells.A small piece of filter paper was placed on the surface of the granule cell layer of the dentate gyrus,which evoked a foreign body reaction of astrocytes,along with the activation of local young neurons expressing doublecortin.Forty-eight hours after foreign body placement,the number of doublecortin-immunoreactive cells increased in the subgranular zone in the direct vicinity of the foreign body,whereas overall increased doublecortin immunoreactivity was observed in the granule cell layer and molecular layer of the dentate gyrus.Foreign body placement in the pyramidal layer of the CA1 region evoked a comparable local astroglial reaction but did not lead to an increase in doublecortin-immunoreactive in either the CA1 region or the adjacent dentate gyrus.Seven days after foreign body placement in the dentate gyrus,the increase in doublecortin-immunoreactivity was no longer observed,indicating the transient activation of young cells.However,7 days after foreign body placement,the number of doublecortin-immunoreactive granule cells coimmunoreactive for calbindin was lower than that under the control conditions.As calbindin is a marker for mature granule cells,this result suggests that activated young cells remain at a more immature stage following foreign body placement.Live imaging of retrovirally green fluorescent protein-labeled newly born granule cells revealed the orientation and growth of their dendrites toward the foreign body placement.This novel experimental model of foreign body placement in organotypic entorhino-hippocampal cultures could serve as a valuable tool for studying both glial reactivity and neuronal plasticity,specifically of newly born neurons under controlled in vitro conditions. 展开更多
关键词 ASTROCYTE brain plasticity dendritic plasticity dentate gyrus focal brain injury hippocampus NEUROPLASTICITY NEUROREPAIR newborn granule cells regeneration REORGANIZATION
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Neuronal plasticity and its role in Alzheimer's disease and Parkinson's disease
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作者 Israt Jahan Mohammad Harun-Ur-Rashid +4 位作者 MdAminul Islam Farhana Sharmin Soad K.Al Jaouni Abdullah M.Kaki Samy Selim 《Neural Regeneration Research》 2026年第1期107-125,共19页
Neuronal plasticity,the brain's ability to adapt structurally and functionally,is essential for learning,memory,and recovery from injuries.In neurodegenerative diseases such as Alzheimer's disease and Parkinso... Neuronal plasticity,the brain's ability to adapt structurally and functionally,is essential for learning,memory,and recovery from injuries.In neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease,this plasticity is disrupted,leading to cognitive and motor deficits.This review explores the mechanisms of neuronal plasticity and its effect on Alzheimer's disease and Parkinson's disease.Alzheimer's disease features amyloid-beta plaques and tau tangles that impair synaptic function,while Parkinson's disease involves the loss of dopaminergic neurons affecting motor control.Enhancing neuronal plasticity offers therapeutic potential for these diseases.A systematic literature review was conducted using databases such as PubMed,Scopus,and Google Scholar,focusing on studies of neuronal plasticity in Alzheimer's disease and Parkinson's disease.Data synthesis identified key themes such as synaptic mechanisms,neurogenesis,and therapeutic strategies,linking molecular insights to clinical applications.Results highlight that targeting synaptic plasticity mechanisms,such as long-term potentiation and long-term depression,shows promise.Neurotrophic factors,advanced imaging techniques,and molecular tools(e.g.,clustered regularly interspaced short palindromic repeats and optogenetics)are crucial in understanding and enhancing plasticity.Current therapies,including dopamine replacement,deep brain stimulation,and lifestyle interventions,demonstrate the potential to alleviate symptoms and improve outcomes.In conclusion,enhancing neuronal plasticity through targeted therapies holds significant promise for treating neurodegenerative diseases.Future research should integrate multidisciplinary approaches to fully harness the therapeutic potential of neuronal plasticity in Alzheimer's disease and Parkinson's disease. 展开更多
关键词 Alzheimer's disease long-term depression long-term potentiation NEUROINFLAMMATION neuronal plasticity Parkinson's disease synaptic plasticity
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Frontal synaptic plasticity:A new key to homeostatic sleep regulation
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作者 Yusuke Iino Shoi Shi 《Neural Regeneration Research》 2026年第6期2313-2314,共2页
Sleep is a fundamental biological process essential for maintaining brain function,cognitive performance,and overall health.Despite over a century of research,the mechanisms underlying sleep homeostasis-the process by... Sleep is a fundamental biological process essential for maintaining brain function,cognitive performance,and overall health.Despite over a century of research,the mechanisms underlying sleep homeostasis-the process by which the need for sleep accumulates during wakefulness and dissipates during sleep-remain incompletely understood.This article explores the latest advancements in sleep research,focusing on the role of synaptic plasticity in sleep homeostasis,as illuminated by Sawada et al.(2024). 展开更多
关键词 homeostatic sleep sleep regulation brain function cognitive performance sleep homeostasis synaptic plasticity frontal synaptic plasticity
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Revisiting Nonlinear Modelling Approaches for Existing RC Structures:Lumped vs.Distributed Plasticity
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作者 Hüseyin Bilgin Bredli Plaku 《Structural Durability & Health Monitoring》 2026年第1期70-85,共16页
Nonlinear static procedures are widely adopted in structural engineering practice for seismic performance assessment due to their simplicity and computational efficiency.However,their reliability depends heavily on ho... Nonlinear static procedures are widely adopted in structural engineering practice for seismic performance assessment due to their simplicity and computational efficiency.However,their reliability depends heavily on how the nonlinear behaviour of structural components is represented.The recent earthquakes in Albania(2019)and Türkiye(2023)have underscored the need for accurate assessment techniques,particularly for older reinforced concrete buildings with poor detailing.This study quantifies the discrepancies between default and user-defined component modelling in pushover analysis of pre-modern reinforced concrete structures,analysing two representative low-and mid-rise reinforced concrete frame buildings.The lumped plasticity approach incorporates moment-rotation relationships derived from actual member properties and reinforcement configurations,while the distributed plasticity approach uses software-generated default properties based on modern codes.Results show that the distributed plasticity models systematically overestimate both the strength and the deformation capacity by up to 35%compared to lumped plasticity models,especially in buildings with poor detailing and low concrete strength.These findings demonstrate that default software procedures,widely used in practice but not validated for pre-modern structures,produce dangerously unconservative seismic performance estimates.The study provides quantitative evidence of the critical need for tailored modelling strategies that reflect the actual conditions of the existing building stock. 展开更多
关键词 Reinforced concrete frames seismic assessment pushover analysis lumped plasticity distributed plasticity
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Photoreforming polylactic acid plastics into pyruvate over CdS/Bi_(4)Ti_(3)O_(12)S-scheme heterojunction:Successive removal of hydrogen fromα-C
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作者 Xinxin Liang Yongqian Cui +6 位作者 Qingyun Tian Tingting Jia Qibing Dong Ximing Li Ting Gao Chao Ma Chuanyi Wang 《Chinese Chemical Letters》 2026年第2期629-634,共6页
Photoreforming poly(lactic acid)(PLA)plastics into pyruvic acid(PA)coupled with hydrogen evolution is of great significance for sustainable development.However,a significant challenge lies inα-OH bond cleaving of lac... Photoreforming poly(lactic acid)(PLA)plastics into pyruvic acid(PA)coupled with hydrogen evolution is of great significance for sustainable development.However,a significant challenge lies inα-OH bond cleaving of lactic acid(LA).Herein,CdS/Bi_(4)Ti_(3)O_(12)composite is fabricated,bridged by Bi−S bonds,through in-situ growth of CdS nanoparticles on Bi_(4)Ti_(3)O_(12)nanoflowers for the successive removal of hydrogen fromα-C in LA.In-situ X-ray photoelectron spectroscopy confirms the S-scheme carriers transfer route and interfacial Bi−S bond in CdS/Bi_(4)Ti_(3)O_(12).Consequently,the photo-electrons and holes with extended lifetimes and strong redox potential accumulate in the CdS conduction band and Bi_(4)Ti_(3)O_(12)valence band,respectively,as evidenced by in-situ electron spin resonance and time-resolved photoluminescence.This facilitates the generation of·OH radicals,which further participate in the successive dehydrogenation reaction of LA.Consequently,the photoreforming efficiencies of converting PLA into PA and H_(2)by CdS/Bi_(4)Ti_(3)O_(12)are 1.7 and 3.16 mmol g^(-1)h^(-1),which are respectively 2.8 and 22 times higher than that by pristine Bi_(4)Ti_(3)O_(12).The present work provides a new approach for designing S-scheme to achieve hydrogen production and value-added conversion of plastics. 展开更多
关键词 H_(2)evolution S-scheme Photoreforming plastic Valuable chemical Plastic oxidation
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Occurrence of microplastics in terrestrial habitats:Hazards and pollution abatement
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作者 Babalola Aisosa ONI Kingsley Chukwunonso AGU Samuel Eshorame SANNI 《Pedosphere》 2026年第1期317-341,共25页
Microplastics(MPs)are ubiquitous and pose an environmental risk.This review examined MP pollution in terrestrial ecosystems from a myriad of poorly understood sources.Knowledge regarding the occurrence sources,migrati... Microplastics(MPs)are ubiquitous and pose an environmental risk.This review examined MP pollution in terrestrial ecosystems from a myriad of poorly understood sources.Knowledge regarding the occurrence sources,migration behaviors,ecotoxicology,absorption mechanisms,and effects of MPs has also been fully summarized.Microplastics interact with contaminants,such as antibiotics,pesticides,heavy metals,etc.,and may act as vectors for contaminant transfer in terrestrial ecosystems.The transportation and retention of MPs in soil are governed by interactions among their inherent properties,such as size,shape,surface charge,and density.Interestingly,MP migration into soil is lacking research.The MPs and nanoplastics were also found in edible fruits and vegetables.The MP contamination in soil affects ecosystems,causing soil structure changes,fertility reduction,and pollutant leaching into groundwater.The MP concentration lies in the range of 43-2443 and 40-43000 items kg-1in agricultural and urban soils,respectively.This review provides a comprehensive roadmap for future research and a framework for soil MP risk assessment.Future studies on the uptake,accumulation,and translocation of MPs and their associated toxins by plants are essential for evaluating their risks to food security and human health.Research on MPs in terrestrial habitats lacks comprehensive data on their long-term persistence,degradation pathways,and interactions with soil components under varying environmental conditions.Additionally,limited understanding exists regarding MP impacts on soil biodiversity,pollutant mobility,and plant uptake,highlighting the need for innovative detection methods and effective pollution abatement strategies. 展开更多
关键词 CONTAMINANT ecological risk macroplastics nanoplastics plastic mulch risk assessment SLUDGE terrestrial ecosystem
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CdS-enzyme composite promotes photobiocatalytic conversion of plastic-derived lactate to chiral chemicals
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作者 Willy W.L.See Phuc T.T.Nguyen +4 位作者 Heng Yih Tan Jie Fu Jeff Zhou Sie Shing Wong Kang Zhou Ning Yan 《Green Energy & Environment》 2026年第2期523-530,共8页
The combination of photo-and bio-catalysis in one-pot enables sustainable,visible-light driven cascade reactions for the synthesis of valueadded chiral chemicals under mild conditions.Despite the attractiveness of mer... The combination of photo-and bio-catalysis in one-pot enables sustainable,visible-light driven cascade reactions for the synthesis of valueadded chiral chemicals under mild conditions.Despite the attractiveness of merging the redox capability of heterogeneous photocatalysts with the excellent enantioselectivity of enzymes,developing such a reaction under one-pot conditions poses a challenge due to catalyst incompatibility.In this study,a cadmium sulfide(CdS)-enzyme composite was engineered for one-pot conversion of plastic-derived lactate into chiral compounds.By coating CdS onto alginate beads,its redox capability for the oxidation of lactate in water under visible light was preserved.The generated pyruvate subsequently underwent enantioselective transformation catalyzed by encapsulated enzymes within the beads,producing(R)-acetoin,L-alanine,or(R)-phenylacetylcarbinol.The core-shell structure of the CdS-enzyme composite protects the enzymes against radical attacks and facilitates recycling,yielding 81% of(R)-acetoin achieved after four reaction cycles.Additionally,we demonstrated an upcycling process converting post-consumer polylactic acid cups into(R)-acetoin.This work introduces a novel approach for integrating photocatalysts and enzymes to synthesize chiral chemicals from end-of-life plastics. 展开更多
关键词 Asymmetric synthesis BIOCATALYSIS PHOTOCATALYSIS Plastic upcycling Organic-inorganic hybrid composites
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Foxg1 and companions:Not only transcription factors
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作者 Antonello Mallamaci Osvaldo Artimagnella Gabriele Liuzzi 《Neural Regeneration Research》 2026年第8期3426-3438,共13页
Moving from the most recent results on Foxg1 biology,we first summarize the available information on some special pleiotropic effectors of neurodevelopmental interest,involved in controlling both transcription and pos... Moving from the most recent results on Foxg1 biology,we first summarize the available information on some special pleiotropic effectors of neurodevelopmental interest,involved in controlling both transcription and post-transcriptional steps of gene expression.Then,after further analysis of the literature,we report evidence that,not strictly limited to neurodevelopmental effectors,such pleiotropy also applies to other transcription factors,involved in physiology and homeostasis.Furthermore,through the systematic analysis of a major public protein-protein interaction database,we gather strong evidence that the involvement of“canonical”transcription factors in post-transcriptional control of gene expression could be a pervasive phenomenon,characterizing hundreds of effectors.Finally,we discuss the biological significance of these findings and propose three evolutionary mechanisms that may have contributed to such an unexpected scenario. 展开更多
关键词 BioGrid co-transcriptional transfer genetic pleiotropy neuronal plasticity POLYADENYLATION protein biosynthesis SPLICING transcription factors triplosensitivity
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Effectiveness of conventional municipal wastewater treatment plants in microplastics removal:Insights from multiple analytical techniques
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作者 Simone Cavazzoli Costanza Scopetani +9 位作者 David Chelazzi Tania Martellini Alessandra Cincinelli Emiliano Carretti Miriam Ascolese Riccardo Gori Karl Mair Werner Tirler Massimo Donegà Gianni Andreottola 《Journal of Environmental Sciences》 2026年第2期424-438,共15页
This study investigated microplastics(MPs)sized 10–5000μm across stages of a conventional municipal wastewater treatment plant using multiple analytical techniques.Samples were collected via pumping and filtration,t... This study investigated microplastics(MPs)sized 10–5000μm across stages of a conventional municipal wastewater treatment plant using multiple analytical techniques.Samples were collected via pumping and filtration,treated with the Fenton reaction for wet peroxidation,and separated by density separation.Analysis employed Focal Plane Array Micro-Fourier Transform Infrared Spectroscopy(FPA micro-FTIR),a widely used technique in MPs analysis,alongside the less common Laser Direct Infrared Spectroscopy(LDIR),providing complementary data on particle composition,shape,size,and colour.To enhance insights,spectroscopic methods were supplemented with Thermal Desorption Gas Chromatography-Mass Spectrometry(TD-GC/MS),calibrated for specific polymers,to quantify MPs by mass and assess removal efficiency.Wastewater treatment effectively reduced MPs.In influent samples,concentrations reached 72 MPs/L(FTIR),2117 MPs/L(LDIR),and 177μg/L(TD-GC/MS).Primary treatments removed 41%–55%,while the wastewater treatment plant effluent contained 1 MPs/L(FTIR),93 MPs/L(LDIR),and 2μg/L(TD-GC/MS),reflecting 96%–99%removal efficiency.Activated sludge showed concentrations of 123 MPs/L(FTIR),10,800 MPs/L(LDIR),and 0.3 mg/g dry weight(TD-GC/MS),underscoring its role in MPs capture.However,sludge dewatering released significant MPs into centrifuge rejected water:484 MPs/L(FTIR),23,000 MPs/L(LDIR),and 1100μg/L(TD-GC/MS).These results highlight the effectiveness of conventional treatments in MPs removal and the critical role of sludge in capturing these contaminants.However,sludge dewatering poses a risk of reintroducing MPs into the environment.Effective sludge management should prioritize nutrient recovery and biomass valorisation to mitigate these risks and minimise harmful environmental impacts. 展开更多
关键词 Emerging contaminant Plastic pollution Analytical method Spectroscopy SPECTROMETRY MPs in WWTPs
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Monocyte Phenotypic Plasticity in Peripheral Artery Disease:From Pathophysiology to Therapeutic Targets
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作者 Gizem Kaynar Beyaz Ahmet Kirbas Sevgi Kalkanli Tas 《BIOCELL》 2026年第1期130-153,共24页
Peripheral artery disease(PAD)remains a significant global health issue,with current treatments primarily focused on relieving symptoms and addressingmacrovascular issues.However,critical immunoinflammatory mechanisms... Peripheral artery disease(PAD)remains a significant global health issue,with current treatments primarily focused on relieving symptoms and addressingmacrovascular issues.However,critical immunoinflammatory mechanisms are often overlooked.Recent evidence suggests that monocyte phenotypic plasticity plays a central role in PAD development,affecting atherogenesis,plaque progression,ischemia-reperfusion injury,and chronic ischemic remodeling.This narrative review aims to summarize the latest advances(2023-2025)in understanding monocyte diversity,functional states,and their changes throughout different stages of PAD.We discuss both established and emerging biomarkers,such as circulating monocyte subset proportions,functional assays,immune checkpoint expression,and multi-omics signatures,highlighting their potential for prognosis and the challenges in translating them to clinical practice.We also present a stage-specific approach to mapping out potential therapies,linking monocyte phenotypes to molecular targets and possible interventions.Additionally,we address regulatory,economic,and implementation considerations for applying these findings in a clinical setting.The goal of this review is to facilitate the development of targeted immunomodulatory strategies to improve limb and cardiovascular outcomes in PAD by combining mechanistic understanding with therapeutic innovation. 展开更多
关键词 Peripheral artery disease MONOCYTES phenotypic plasticity IMMUNOMODULATION therapeutic targets
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