Low-density superalloys often exhibit low yield strength in the intermediate temperature range(300−650℃).To enhance yield performance in this range,the CALPHAD method was used to design a new Co-based superalloy.The ...Low-density superalloys often exhibit low yield strength in the intermediate temperature range(300−650℃).To enhance yield performance in this range,the CALPHAD method was used to design a new Co-based superalloy.The Co−30Ni−10Al−3V−6Ti−2Ta alloy,designed based onγʹphase dissolution temperature and phase fraction,was synthesized via arc melting and heat treatment.Phase transition temperatures,microstructure evolution,and hightemperature mechanical properties were characterized by differential scanning calorimetry,scanning electron microscopy,dual-beam TEM,and compression tests.Results show that the alloy has low density(8.15 g/cm^(3))and highγʹdissolution temperature(1234℃),along with unique yield strength retention from room temperature to 650℃.The yield strength anomaly(YSA)is attributed to high stacking fault energy and activation of the Kear−Wilsdorf locking mechanism,contributing to superior high-temperature stability of the alloy.The yield strength of this alloy outperforms other lowdensity Co-based superalloys in the temperature range of 23−650℃.展开更多
The Co-Ni-Ti-V quaternary phase diagrams within the Co-Ni-rich region were investigated using the electron probe X-ray micro-analyzer(EPMA)and X-ray diffraction(XRD).Three isothermal sections corresponding to the Co-1...The Co-Ni-Ti-V quaternary phase diagrams within the Co-Ni-rich region were investigated using the electron probe X-ray micro-analyzer(EPMA)and X-ray diffraction(XRD).Three isothermal sections corresponding to the Co-10Ni-Ti-V,Co-15Ni-Ti-V,and Co-20Ni-Ti-V quaternary systems at 1000°C were experimentally established.The results indicate that increasing Ni content markedly broadens theγ(α-Co)andγ′(Co3Ti)two-phase regions.Based on the Co-Ni-Ti-V phase diagram,alloys with highγ′solvus temperature were designed,and their comprehensive properties,includingγ′coarsening behavior and mechanical properties,were thoroughly investigated.Compared to Co-Ti-based superalloys,the Co-20Ni-10Ti-10V alloy exhibits lower coarsening rates ofγ′precipitates andγ/γ′lattice mismatch.Notably,it possesses exceptional high-temperature mechanical properties,with a yield strength of 508 MPa at 1000°C.This superior performance is primarily attributed to the presence of a high density of stacking fault shear.展开更多
U-Net has achieved good performance with the small-scale datasets through skip connections to merge the features of the low-level layers and high-level layers and has been widely utilized in biomedical image segmentat...U-Net has achieved good performance with the small-scale datasets through skip connections to merge the features of the low-level layers and high-level layers and has been widely utilized in biomedical image segmentation as well as recent microstructure image segregation of the materials.Three representative visual attention mechanism modules,named as squeeze-and-excitation networks,convolutional block attention module,and extended calibration algorithm,were intro-duced into the traditional U-Net architecture to further improve the prediction accuracy.It is found that compared with the original U-Net architecture,the evaluation index of the improved U-Net architecture has been significantly improved for the microstructure segmentation of the steels with the ferrite/martensite composite microstructure and pearlite/ferrite composite microstructure and the complex martensite/austenite island/bainite microstructure,which demonstrates the advantages of the utilization of the visual attention mechanism in the microstructure segregation.The reasons for the accuracy improvement were discussed based on the feature maps analysis.展开更多
Objective:Based on the technology and method of network pharmacology,to explore the active components and specific mechanism of Simiao powder in the treatment of synovitis.Methods:by using tcmsp database,the potential...Objective:Based on the technology and method of network pharmacology,to explore the active components and specific mechanism of Simiao powder in the treatment of synovitis.Methods:by using tcmsp database,the potential active components and related target proteins of Simiao powder were screened.Genecards and digenet database were used to predict the target of synovitis.UniProt database was used to query the corresponding gene names.The compound synovitis target network and protein of Simiao powder were constructed by using Cytoscape and string software In R language,bio conductor data package was used to analyze the enrichment of go biological function and KEGG pathway,and the effective components and targets of Simiao powder in the treatment of synovitis were obtained.Results:64 key active components of Simiao powder were screened out from tcmsp database,71 of them were involved in the interaction of main chemical components of Simiao powder-chemical components and synovitis treatment target-synovitis.95 PPI core genes were obtained,and 90 go biological enrichment processes were obtained by go enrichment analysis.The results of network pharmacology indicate that Simiaosan can regulate 32 signaling pathways in the treatment of synovitis,including IL-17 signaling pathway,TNF signaling pathway,T cell receptor signaling pathway and toll like receptor signaling pathway.Conclusion:the treatment of synovitis with Simiao powder is a complex process of multi-component,multi-target and multi-channel,which is related to the coordinated regulation of multiple targets and signal pathways.展开更多
In this work,we investigate the numerical evolution of massive Kaluza–Klein(KK)modes of a Dirac field on a thick brane.We deduce the Dirac equation in five-dimensional spacetime,and obtain the time-dependent evolutio...In this work,we investigate the numerical evolution of massive Kaluza–Klein(KK)modes of a Dirac field on a thick brane.We deduce the Dirac equation in five-dimensional spacetime,and obtain the time-dependent evolution equation and Schr?dinger-like equation of the extradimensional component.We use the Dirac KK resonances as the initial data and study the corresponding dynamics.By monitoring the decay law of the left-and right-chiral KK resonances,we compute the corresponding lifetimes and find that there could exist long-lived KK modes on the brane.Especially,for the lightest KK resonance with a large coupling parameter and a large three momentum,it will have an extremely long lifetime.展开更多
In this study,we focus on the gravitational waves emitted by a stellar-mass object in a quasi-circular inspiral orbit around a central supermassive polymerized black hole in loop quantum gravity.Treating the stellar-m...In this study,we focus on the gravitational waves emitted by a stellar-mass object in a quasi-circular inspiral orbit around a central supermassive polymerized black hole in loop quantum gravity.Treating the stellar-mass object as a massive test particle,we derive its equations of motion and the corresponding radial effective potential.We find that the peak of the radial effective potential decreases with the quantum parameter k.We also examine the impact of quantum corrections on the properties of stable circular orbits(SCOs)around the polymerized black hole.We model the smaller object's trajectory as an adiabatic evolution along SCOs using a semi-relativistic approach.In this method,the motion of the object is described by relativistic geodesics,and changes in the object's energy and orbital angular momentum due to gravitational radiation are calculated using the mass quadrupole formula.The corresponding gravitational waveforms are generated using the numerical kludge method,revealing that quantum corrections cause phase advances in the gravitational waveforms.We further analyze the potential constraints on the quantum parameter k from future space-based gravitational wave observations,concluding that the constraints on k imposed by these observations will likely be stronger than those imposed by black hole shadow measurements.展开更多
Graphene-plasmonic hybrid platforms have attracted an enormous amount of interest in surface-enhanced Raman scattering(SERS);however,the mechanism of employing graphene is still ambiguous,so clarification about the co...Graphene-plasmonic hybrid platforms have attracted an enormous amount of interest in surface-enhanced Raman scattering(SERS);however,the mechanism of employing graphene is still ambiguous,so clarification about the complex interaction among molecules,graphene,and plasmon processes is urgently needed.We report that the number of graphene layers controlled the plasmon-driven,surface-catalyzed reaction that converts para-aminothiophenol(PATP)-to-p,p'-dimercaptoazobenzene(DMAB)on chemically inert,graphene-coated,silver bowtie nanoantenna arrays.The catalytic reaction was monitored by SERS,which revealed that the catalytic reaction occurred on the chemical inertness monolayer graphene(1G)-coated silver nanostructures.The introduction of 1G enhances the plasmon-driven surface-catalyzed reaction of the conversion of PATP-to-p,p'-DMAB.The chemical reaction is suppressed by bilayer graphene.In the process of the catalytic reaction,the electron transfer from the PATP molecule to 1G-coated silver nanostructures.Subsequently,the transferred electrons on the graphene recombine with the hot-hole produced by the localized surface plasmon resonance of silver nanostructures.Then,a couple of PATP molecules lost electrons are catalyzed into the p,p'-DMAB molecule on the graphene surface.The experimental results were further supported by the finite-difference time-domain method and quantum chemical calculations.展开更多
基金supported by the National Natural Science Foundation of China(Nos.51831007,52101135)the Shenzhen Science and Technology Program,China(No.SGDX20210823104002016)the Guangdong Basic and Applied Basic Research Foundation,China(Nos.2021B1515120071,JCYJ20220531095217039)。
文摘Low-density superalloys often exhibit low yield strength in the intermediate temperature range(300−650℃).To enhance yield performance in this range,the CALPHAD method was used to design a new Co-based superalloy.The Co−30Ni−10Al−3V−6Ti−2Ta alloy,designed based onγʹphase dissolution temperature and phase fraction,was synthesized via arc melting and heat treatment.Phase transition temperatures,microstructure evolution,and hightemperature mechanical properties were characterized by differential scanning calorimetry,scanning electron microscopy,dual-beam TEM,and compression tests.Results show that the alloy has low density(8.15 g/cm^(3))and highγʹdissolution temperature(1234℃),along with unique yield strength retention from room temperature to 650℃.The yield strength anomaly(YSA)is attributed to high stacking fault energy and activation of the Kear−Wilsdorf locking mechanism,contributing to superior high-temperature stability of the alloy.The yield strength of this alloy outperforms other lowdensity Co-based superalloys in the temperature range of 23−650℃.
基金supported by the National Natural Science Foundation of China(Nos.51831007,52371007)the Shenzhen Science and Technology Program,China(No.SGDX20210823104002016)the Guangdong Basic and Applied Basic Research Foundation,China(No.2021B1515120071).
文摘The Co-Ni-Ti-V quaternary phase diagrams within the Co-Ni-rich region were investigated using the electron probe X-ray micro-analyzer(EPMA)and X-ray diffraction(XRD).Three isothermal sections corresponding to the Co-10Ni-Ti-V,Co-15Ni-Ti-V,and Co-20Ni-Ti-V quaternary systems at 1000°C were experimentally established.The results indicate that increasing Ni content markedly broadens theγ(α-Co)andγ′(Co3Ti)two-phase regions.Based on the Co-Ni-Ti-V phase diagram,alloys with highγ′solvus temperature were designed,and their comprehensive properties,includingγ′coarsening behavior and mechanical properties,were thoroughly investigated.Compared to Co-Ti-based superalloys,the Co-20Ni-10Ti-10V alloy exhibits lower coarsening rates ofγ′precipitates andγ/γ′lattice mismatch.Notably,it possesses exceptional high-temperature mechanical properties,with a yield strength of 508 MPa at 1000°C.This superior performance is primarily attributed to the presence of a high density of stacking fault shear.
基金support from National Natural Science Foundation of China(Nos.52071238 and U20A20279)National Key Research and Development Program of China(2022YFB3706701)the 111 Project(No.D18018)。
文摘U-Net has achieved good performance with the small-scale datasets through skip connections to merge the features of the low-level layers and high-level layers and has been widely utilized in biomedical image segmentation as well as recent microstructure image segregation of the materials.Three representative visual attention mechanism modules,named as squeeze-and-excitation networks,convolutional block attention module,and extended calibration algorithm,were intro-duced into the traditional U-Net architecture to further improve the prediction accuracy.It is found that compared with the original U-Net architecture,the evaluation index of the improved U-Net architecture has been significantly improved for the microstructure segmentation of the steels with the ferrite/martensite composite microstructure and pearlite/ferrite composite microstructure and the complex martensite/austenite island/bainite microstructure,which demonstrates the advantages of the utilization of the visual attention mechanism in the microstructure segregation.The reasons for the accuracy improvement were discussed based on the feature maps analysis.
基金Liaoning Province TCM rehabilitation discipline construction project(No.10010239a00175)。
文摘Objective:Based on the technology and method of network pharmacology,to explore the active components and specific mechanism of Simiao powder in the treatment of synovitis.Methods:by using tcmsp database,the potential active components and related target proteins of Simiao powder were screened.Genecards and digenet database were used to predict the target of synovitis.UniProt database was used to query the corresponding gene names.The compound synovitis target network and protein of Simiao powder were constructed by using Cytoscape and string software In R language,bio conductor data package was used to analyze the enrichment of go biological function and KEGG pathway,and the effective components and targets of Simiao powder in the treatment of synovitis were obtained.Results:64 key active components of Simiao powder were screened out from tcmsp database,71 of them were involved in the interaction of main chemical components of Simiao powder-chemical components and synovitis treatment target-synovitis.95 PPI core genes were obtained,and 90 go biological enrichment processes were obtained by go enrichment analysis.The results of network pharmacology indicate that Simiaosan can regulate 32 signaling pathways in the treatment of synovitis,including IL-17 signaling pathway,TNF signaling pathway,T cell receptor signaling pathway and toll like receptor signaling pathway.Conclusion:the treatment of synovitis with Simiao powder is a complex process of multi-component,multi-target and multi-channel,which is related to the coordinated regulation of multiple targets and signal pathways.
基金supported by the National Key Research and Development Program of China(Grant No.2020YFC2201503)the National Natural Science Foundation of China(Grants No.12105126,No.11875151,and No.12247101)+3 种基金the 111Project under(Grant No.B20063)the Fundamental Research Funds for the Central Universities(Grant No.lzujbky2021-pd08)the China Postdoctoral Science Foundation(Grant No.2021M701531)‘Lanzhou City’s scientific research funding subsidy to Lanzhou University’。
文摘In this work,we investigate the numerical evolution of massive Kaluza–Klein(KK)modes of a Dirac field on a thick brane.We deduce the Dirac equation in five-dimensional spacetime,and obtain the time-dependent evolution equation and Schr?dinger-like equation of the extradimensional component.We use the Dirac KK resonances as the initial data and study the corresponding dynamics.By monitoring the decay law of the left-and right-chiral KK resonances,we compute the corresponding lifetimes and find that there could exist long-lived KK modes on the brane.Especially,for the lightest KK resonance with a large coupling parameter and a large three momentum,it will have an extremely long lifetime.
基金Supported by the National Key Research and Development Program of China(2021YFC2203003)the National Natural Science Foundation of China(12475056,12105126,12275238,12247101)+2 种基金the National Natural Science Foundation of Gansu Province(22JR5RA389)the‘111 Center'(B20063),the Zhejiang Provincial Natural Science Foundation of China(LR21A050001,LY20A050002)the Fundamental Research Funds for the Provincial Universities of Zhejiang in China(RF-A2019015)。
文摘In this study,we focus on the gravitational waves emitted by a stellar-mass object in a quasi-circular inspiral orbit around a central supermassive polymerized black hole in loop quantum gravity.Treating the stellar-mass object as a massive test particle,we derive its equations of motion and the corresponding radial effective potential.We find that the peak of the radial effective potential decreases with the quantum parameter k.We also examine the impact of quantum corrections on the properties of stable circular orbits(SCOs)around the polymerized black hole.We model the smaller object's trajectory as an adiabatic evolution along SCOs using a semi-relativistic approach.In this method,the motion of the object is described by relativistic geodesics,and changes in the object's energy and orbital angular momentum due to gravitational radiation are calculated using the mass quadrupole formula.The corresponding gravitational waveforms are generated using the numerical kludge method,revealing that quantum corrections cause phase advances in the gravitational waveforms.We further analyze the potential constraints on the quantum parameter k from future space-based gravitational wave observations,concluding that the constraints on k imposed by these observations will likely be stronger than those imposed by black hole shadow measurements.
基金This work was partially supported by the NSFC(51171132,U1260102,51371131,11375134,11374353,and 91436102),NCET(12-0418)Hubei Provincial Natural Science Foundation(2011CDB270,2012FFA042)+2 种基金Jiangsu Provincial Natural Science Foundation(BK20141217)Wuhan Planning Project of Science and Technology(2014010101010019)the Wuhan University Experiment Technology Project Funding,the Fundamental Research Funds for the Central Universities(2042015kf1012,2042015gf0016)
文摘Graphene-plasmonic hybrid platforms have attracted an enormous amount of interest in surface-enhanced Raman scattering(SERS);however,the mechanism of employing graphene is still ambiguous,so clarification about the complex interaction among molecules,graphene,and plasmon processes is urgently needed.We report that the number of graphene layers controlled the plasmon-driven,surface-catalyzed reaction that converts para-aminothiophenol(PATP)-to-p,p'-dimercaptoazobenzene(DMAB)on chemically inert,graphene-coated,silver bowtie nanoantenna arrays.The catalytic reaction was monitored by SERS,which revealed that the catalytic reaction occurred on the chemical inertness monolayer graphene(1G)-coated silver nanostructures.The introduction of 1G enhances the plasmon-driven surface-catalyzed reaction of the conversion of PATP-to-p,p'-DMAB.The chemical reaction is suppressed by bilayer graphene.In the process of the catalytic reaction,the electron transfer from the PATP molecule to 1G-coated silver nanostructures.Subsequently,the transferred electrons on the graphene recombine with the hot-hole produced by the localized surface plasmon resonance of silver nanostructures.Then,a couple of PATP molecules lost electrons are catalyzed into the p,p'-DMAB molecule on the graphene surface.The experimental results were further supported by the finite-difference time-domain method and quantum chemical calculations.
