Among all the structural formations,fiber-like structure is one of the most common modalities in organisms that undertake essential functions.Alterations in spatial organization of fibrous structures can refiect infor...Among all the structural formations,fiber-like structure is one of the most common modalities in organisms that undertake essential functions.Alterations in spatial organization of fibrous structures can refiect information of physiological and pathological activities,which is of significance in both researches and clinical applications.Hence,the quantification of subtle changes in fiber-like structures is potentiallymeaningful in studying structure-function relationships,disease progression,carcinoma staging and engineered tissue remodeling.In this study,we examined a wide range of methodologies that quantify organizational and morphological features of fibrous structures,including orientation,alignment,waviness and thickness.Each method was demonstrated with specific applications.Finally,perspectives of future quantification analysis techniques were explored.展开更多
According to the principle that fiber-like arrangement of reinforcing particles SnO2 paralleling to the direction of current is propitious to the electrical and mechanical performance of the electrical contact materia...According to the principle that fiber-like arrangement of reinforcing particles SnO2 paralleling to the direction of current is propitious to the electrical and mechanical performance of the electrical contact materials, we proposed and reported a novel precursor route used to prepare Ag/SnO,. electrical contact material with fiber- like arrangement of reinforcing nanoparticles. The mechanism for the formation of fiber-like arrangement of rein- forcing nanoparticles in Ag/SnO2 electrical contact material was also discussed. The as-prepared samples were char- acterized by means of scanning electron microscope （SEM）, optical microscope （OM）, energy-dispersive X-ray spectroscopy （EDX）, MHV2000 microhardness test, and double bridge tester. The analysis showed that the as-prepared Ag/SnO,, electrical contact material with fiber-like arrangement of reinforcing nanoparticles exhibits a high elongation of 24 %, a particularly low electrical resistivity of 2.08 μΩ. cm, and low arcing energy, and thus has considerable technical, economical and environmental benefits.展开更多
Property characterization of nanomaterials is challenged by the small size of the structure be-cause of the difficulties in manipulation Here we demonstrate a novel approach that allows a direct measurement of the mec...Property characterization of nanomaterials is challenged by the small size of the structure be-cause of the difficulties in manipulation Here we demonstrate a novel approach that allows a direct measurement of the mechanical properties of individual nanotube-like structures by in-situ transmission electron microscopy (TEM). The technique is powerful in a way that it can directly correlate the atomic-scale microstructure of the carbon nanotube with its physical properties, providing a one-to-one correspondence in structure-property characterization Applications of the technique will be demonstrated on mechanical properties, the electron field emission and the ballistic quantum conductance in individual nanotubes.展开更多
Flher-like particle suspensions are common in both na-ture and industry, but there is little work reported on it.The forces acting on the fiber - like particle in fluid arestudied in this paper, and the Magnus lift, S...Flher-like particle suspensions are common in both na-ture and industry, but there is little work reported on it.The forces acting on the fiber - like particle in fluid arestudied in this paper, and the Magnus lift, Saffman lift,pressure gradient force, and then the dynamics modelhave been received. The numerical study of the simpleshear flow past the cylinders shows that the particles ’motion is controlled by the vortex.展开更多
Fiber-like particle suspensions are common in both nature and industry, yet research on them is still in its infancy. This paper focuses on the theoretical analysis of the heat-swimming force operating on the fiber-li...Fiber-like particle suspensions are common in both nature and industry, yet research on them is still in its infancy. This paper focuses on the theoretical analysis of the heat-swimming force operating on the fiber-like particle in nonconformity temperature fluid, and the approximate calculating formula has been proposed. It is indicated that the heat- swimming force on the fiber-like particle is in direct proportion to thetemperature gradient of fluid, but it has opposite direction and that it is restrained by the particle volume, the fluid viscosity and density rather than by the particle density.展开更多
The lamellar layer of intermetallic compounds(IMCs)was adversely affected the performance of welding-brazing joints in Al/steel dissimilar metals.In this study,a short fiber-like surface morphology was fabricated on t...The lamellar layer of intermetallic compounds(IMCs)was adversely affected the performance of welding-brazing joints in Al/steel dissimilar metals.In this study,a short fiber-like surface morphology was fabricated on the butt surface of Q235 steel via laser.The interaction behavior between the short fibers and the molten pool was captured using a high-speed camera.Laser-arc hybrid welding-brazing was then employed to join Al(6061-T6)to the steel.This process successfully created a short fiber-like interface structure at the joint.The relationship between microstructure and mechanical properties was investigated,compared with Al/bare steel(ABS)joint.The research results indicated that the IMCs layer consisted of FeAl_(3)and Fe_(2)Al_(5).The interface strength of the Al/short fiber-like surface structural steel(ASFSSS)joint reached 153.2 MPa,an 82.2%increase compared to the ABS joint,which reached 84.1 MPa.When the ASFSSS joints without the reinforcement were bent to 58.2°and 25.2°in the longitudinal and transverse direction,respectively,they remained intact.However,cracks were discovered when the bending angle of the ABS reached 39.1°and 0°in the two directions.Numerical simulation revealed that the short fiber-like interface structure significantly reduced residual stress and improved the stress distribution in the weld,thereby enhancing the strength and toughness of Al/steel dissimilar joints.The crack propagation path in the ASFSSS joint was deflected into the weld when it encountered short fibers,and the fracture morphology presented the characteristic of ductile-brittle mixed fracture.展开更多
Ti_(3)C_(2)T_(x) nanosheets have attracted significant attention for their potential in electromagnetic wave absorption(EWA).However,their inherent self-stacking and exorbitant electrical conductivity inevitably lead ...Ti_(3)C_(2)T_(x) nanosheets have attracted significant attention for their potential in electromagnetic wave absorption(EWA).However,their inherent self-stacking and exorbitant electrical conductivity inevitably lead to serious impedance mismatch,restricting their EWA application.Therefore,the optimization of impedance matching becomes crucial.In this work,we developed polymethyl methacrylate(PMMA)@Ti_(3)C_(2)T_(x)@SiO_(2) composites with a sandwich-like core–shell structure by coating SiO_(2) on PMMA@Ti_(3)C_(2)T_(x).The results demonstrate that the superiority of the SiO_(2) layer in combination with PMMA@Ti_(3)C_(2)T_(x),outperforming other relative graded distribution structures and meeting the requirements of EWA equipment.The resulting PMMA@Ti_(3)C_(2)T_(x)@SiO_(2) composites achieved a minimum reflection loss of-58.08 dB with a thickness of 1.9 mm,and an effective absorption bandwidth of 2.88 GHz.Mechanism analysis revealed that the structural design of SiO_(2) layer not only optimized impedance matching,but also synergistically enhanced multiple loss mechanisms such as interfacial polarization and dipolar polarization.Therefore,this work provides valuable insights for the future preparation of high-performance electromagnetic wave absorbing Ti_(3)C_(2)T_(x)-based composites.展开更多
Fragmentation/disassembly of fiber-like micelles generated by living crystalline-driven self-assembly(CDSA)is usually encountered in aqueous media,which hinders the applications of micelles.Herein,we report the genera...Fragmentation/disassembly of fiber-like micelles generated by living crystalline-driven self-assembly(CDSA)is usually encountered in aqueous media,which hinders the applications of micelles.Herein,we report the generation of uniform fiber-like micelles consisting of a𝜋Л-conjugated oligo(p-phenylenevinylene)core and a crosslinking silica shell with grafted poly(ethylene glycol)(PEG)chains by the combination of living CDSA,silica chemistry and surface grafting-onto strategy.Owing to the presence of crosslinking silica shell and the outmost PEG chains,the resulting micelles exhibit excellent dispersity and colloidal stability in PBS buffer,BSA aqueous solution and upon heating at 80℃ for 2 h without micellar fragmentation/disassembly.The micelles also show negligible cytotoxicity toward both HeLa cervical cancer and HEK239T human embryonic kidney cell lines.Interestingly,micelles with Ln of 156 nm show the“stealth”property with no significant uptake by HeLa cells,whereas some certain amounts of micelles with Ln of 535 nm can penetrate into HeLa cells,showing length-dependent cellular uptake behaviors.These results provide a route to prepare uniform,colloidally stable fiber-like nanostructures with tunable length and functions derived for biomedical applications.展开更多
基金supported by National Key Research and Development Program of China (2019YFE0113700 and 2017YFA0700501)National Natural Science Foundation of China (61905214,62035011,11974310 and 31927801)Natural Science Foundation of Zhejiang Province (LR20F050001).
文摘Among all the structural formations,fiber-like structure is one of the most common modalities in organisms that undertake essential functions.Alterations in spatial organization of fibrous structures can refiect information of physiological and pathological activities,which is of significance in both researches and clinical applications.Hence,the quantification of subtle changes in fiber-like structures is potentiallymeaningful in studying structure-function relationships,disease progression,carcinoma staging and engineered tissue remodeling.In this study,we examined a wide range of methodologies that quantify organizational and morphological features of fibrous structures,including orientation,alignment,waviness and thickness.Each method was demonstrated with specific applications.Finally,perspectives of future quantification analysis techniques were explored.
基金National Major Scientific&Technological Achievement Transformation Project
文摘According to the principle that fiber-like arrangement of reinforcing particles SnO2 paralleling to the direction of current is propitious to the electrical and mechanical performance of the electrical contact materials, we proposed and reported a novel precursor route used to prepare Ag/SnO,. electrical contact material with fiber- like arrangement of reinforcing nanoparticles. The mechanism for the formation of fiber-like arrangement of rein- forcing nanoparticles in Ag/SnO2 electrical contact material was also discussed. The as-prepared samples were char- acterized by means of scanning electron microscope （SEM）, optical microscope （OM）, energy-dispersive X-ray spectroscopy （EDX）, MHV2000 microhardness test, and double bridge tester. The analysis showed that the as-prepared Ag/SnO,, electrical contact material with fiber-like arrangement of reinforcing nanoparticles exhibits a high elongation of 24 %, a particularly low electrical resistivity of 2.08 μΩ. cm, and low arcing energy, and thus has considerable technical, economical and environmental benefits.
文摘Property characterization of nanomaterials is challenged by the small size of the structure be-cause of the difficulties in manipulation Here we demonstrate a novel approach that allows a direct measurement of the mechanical properties of individual nanotube-like structures by in-situ transmission electron microscopy (TEM). The technique is powerful in a way that it can directly correlate the atomic-scale microstructure of the carbon nanotube with its physical properties, providing a one-to-one correspondence in structure-property characterization Applications of the technique will be demonstrated on mechanical properties, the electron field emission and the ballistic quantum conductance in individual nanotubes.
基金Supported by the financial of the Natural Science Fund for outatending youth of China and the fund fo the state key laboratory of fluid transreiasion and control of Zhejiand University
文摘Flher-like particle suspensions are common in both na-ture and industry, but there is little work reported on it.The forces acting on the fiber - like particle in fluid arestudied in this paper, and the Magnus lift, Saffman lift,pressure gradient force, and then the dynamics modelhave been received. The numerical study of the simpleshear flow past the cylinders shows that the particles ’motion is controlled by the vortex.
基金Supported by the Natural Science Toundation for outstanding youth of China and the State Key Laboratory of Fluid Transmission and Control of Zhejiang University
文摘Fiber-like particle suspensions are common in both nature and industry, yet research on them is still in its infancy. This paper focuses on the theoretical analysis of the heat-swimming force operating on the fiber-like particle in nonconformity temperature fluid, and the approximate calculating formula has been proposed. It is indicated that the heat- swimming force on the fiber-like particle is in direct proportion to thetemperature gradient of fluid, but it has opposite direction and that it is restrained by the particle volume, the fluid viscosity and density rather than by the particle density.
基金supported by the National Natural Science Foundation of China(No.52275306)the Beijing Municipal Natural Science Foundation(No.3232021).
文摘The lamellar layer of intermetallic compounds(IMCs)was adversely affected the performance of welding-brazing joints in Al/steel dissimilar metals.In this study,a short fiber-like surface morphology was fabricated on the butt surface of Q235 steel via laser.The interaction behavior between the short fibers and the molten pool was captured using a high-speed camera.Laser-arc hybrid welding-brazing was then employed to join Al(6061-T6)to the steel.This process successfully created a short fiber-like interface structure at the joint.The relationship between microstructure and mechanical properties was investigated,compared with Al/bare steel(ABS)joint.The research results indicated that the IMCs layer consisted of FeAl_(3)and Fe_(2)Al_(5).The interface strength of the Al/short fiber-like surface structural steel(ASFSSS)joint reached 153.2 MPa,an 82.2%increase compared to the ABS joint,which reached 84.1 MPa.When the ASFSSS joints without the reinforcement were bent to 58.2°and 25.2°in the longitudinal and transverse direction,respectively,they remained intact.However,cracks were discovered when the bending angle of the ABS reached 39.1°and 0°in the two directions.Numerical simulation revealed that the short fiber-like interface structure significantly reduced residual stress and improved the stress distribution in the weld,thereby enhancing the strength and toughness of Al/steel dissimilar joints.The crack propagation path in the ASFSSS joint was deflected into the weld when it encountered short fibers,and the fracture morphology presented the characteristic of ductile-brittle mixed fracture.
基金supported by the National Natural Science Foundation of China(No.U2004177)Henan Province Key Research Project for Higher Education Institutions(No.23B430017)+1 种基金the Outstanding Youth Fund of Henan Province(No.212300410081)the Science and Technology Innovation Talents in Universities of Henan Province(No.22HASTIT001).
文摘Ti_(3)C_(2)T_(x) nanosheets have attracted significant attention for their potential in electromagnetic wave absorption(EWA).However,their inherent self-stacking and exorbitant electrical conductivity inevitably lead to serious impedance mismatch,restricting their EWA application.Therefore,the optimization of impedance matching becomes crucial.In this work,we developed polymethyl methacrylate(PMMA)@Ti_(3)C_(2)T_(x)@SiO_(2) composites with a sandwich-like core–shell structure by coating SiO_(2) on PMMA@Ti_(3)C_(2)T_(x).The results demonstrate that the superiority of the SiO_(2) layer in combination with PMMA@Ti_(3)C_(2)T_(x),outperforming other relative graded distribution structures and meeting the requirements of EWA equipment.The resulting PMMA@Ti_(3)C_(2)T_(x)@SiO_(2) composites achieved a minimum reflection loss of-58.08 dB with a thickness of 1.9 mm,and an effective absorption bandwidth of 2.88 GHz.Mechanism analysis revealed that the structural design of SiO_(2) layer not only optimized impedance matching,but also synergistically enhanced multiple loss mechanisms such as interfacial polarization and dipolar polarization.Therefore,this work provides valuable insights for the future preparation of high-performance electromagnetic wave absorbing Ti_(3)C_(2)T_(x)-based composites.
基金The authors are thankful for financial support from National Science Foundation for Distinguished Young Scholars(51825304)National Natural Science Foundation of China(52122314,51873229 and 51961145103)+3 种基金the project of Bureau of International Cooperation,CAS(121731KYSB20200006)Youth Innovation Promotion Association of CAS(Y2020062)Shanghai Scientific and Technological Innovation Project(19ZR1468400,19590750400,20JC1415400 and 21520780100)Innovation Program of Shanghai Municipal Education Commission(2019-01-07-00-05-E00012).
文摘Fragmentation/disassembly of fiber-like micelles generated by living crystalline-driven self-assembly(CDSA)is usually encountered in aqueous media,which hinders the applications of micelles.Herein,we report the generation of uniform fiber-like micelles consisting of a𝜋Л-conjugated oligo(p-phenylenevinylene)core and a crosslinking silica shell with grafted poly(ethylene glycol)(PEG)chains by the combination of living CDSA,silica chemistry and surface grafting-onto strategy.Owing to the presence of crosslinking silica shell and the outmost PEG chains,the resulting micelles exhibit excellent dispersity and colloidal stability in PBS buffer,BSA aqueous solution and upon heating at 80℃ for 2 h without micellar fragmentation/disassembly.The micelles also show negligible cytotoxicity toward both HeLa cervical cancer and HEK239T human embryonic kidney cell lines.Interestingly,micelles with Ln of 156 nm show the“stealth”property with no significant uptake by HeLa cells,whereas some certain amounts of micelles with Ln of 535 nm can penetrate into HeLa cells,showing length-dependent cellular uptake behaviors.These results provide a route to prepare uniform,colloidally stable fiber-like nanostructures with tunable length and functions derived for biomedical applications.
