The effect of inner-surface roughness of conical targets on the generation of fast electrons in the laser-cone interaction is investigated using particle-in-cell simulation. It is found that the surface roughness can ...The effect of inner-surface roughness of conical targets on the generation of fast electrons in the laser-cone interaction is investigated using particle-in-cell simulation. It is found that the surface roughness can reduce the fast-electron number (in the energy range E 〉 1 MeV) and energy, as compared to that from a cone with smooth inner wall. A scaling law for the laser reflectivity based on the vacuum-heating model is derived. Both theory and simulation indicate that laser reflection increases with the height-to-width ratio of the periodic inner surface structure and approaches that of a smooth cone as this ratio becomes zero.展开更多
In the present investigation, a pipe inner-surface grinding(PISG) technique was developed to fabricate nanostructure in the inner-surface of an austenitic 304 stainless steel pipe. PISG was performed by high speed s...In the present investigation, a pipe inner-surface grinding(PISG) technique was developed to fabricate nanostructure in the inner-surface of an austenitic 304 stainless steel pipe. PISG was performed by high speed shearing with hard sphere tips, leading to gradient distribution of strain, strain rate and strain gradient along depth. Nano-austenite with an average boundary spacing of 20 nm was generated, followed by deformation microstructure characterized by shear bands, multi-and uni-directional twins and planar dislocation arrays. Deformation induced grain refinement of austenitic 304 stainless steel with low stacking fault energy(SFE) covering 4–5 order's magnitude of length scales toward nanometer regime was unified.展开更多
Two novel anionic single-walled metal-organic nanotubes(MONTs),[(CH_(3))_(2)NH_(2)][ln(cdc)(thb)].2DMF.9.5H_(2)O(FJU-105)and[(CH_(3))_(2)NH_(2)][ln(cdc)(H-btc)]-2DMA·11H_(2)O(FJU-106)(H_(2)cdc=9H-carbazole-3,6-di...Two novel anionic single-walled metal-organic nanotubes(MONTs),[(CH_(3))_(2)NH_(2)][ln(cdc)(thb)].2DMF.9.5H_(2)O(FJU-105)and[(CH_(3))_(2)NH_(2)][ln(cdc)(H-btc)]-2DMA·11H_(2)O(FJU-106)(H_(2)cdc=9H-carbazole-3,6-dicarboxylic acid,H_(2)thb=2,5-thiophene dicarboxylic acid,H3btc=1,3,5-benzene tricarboxylic acid),are achieved by employing[ln_(6)(cdc)_(6)]^(6+)metalloring cluster with largest diameter as the secondary building blocks(SBUs).The inner surface of FJU-106 is functionalized by uncoordinated-COOH groups of the H-btc linkers,leading to a higher proton conduction than FJU-105.At 70℃,FJU-106 displays the proton conduction performances among MONTs,up to 1.80×10^(-2)S·cm(^-1).And FJU-105 and FJU-106 are the first examples of MONT proton conductors operating at subzero temperature.展开更多
In the present investigation,an austenitic AISI 304 stainless steel was subjected to high strain rate surface deformation by Pipe Inner-Surface Grinding(PISG)technique.The depth-dependent deformation parameters(strain...In the present investigation,an austenitic AISI 304 stainless steel was subjected to high strain rate surface deformation by Pipe Inner-Surface Grinding(PISG)technique.The depth-dependent deformation parameters(strain,strain rate and strain gradient)were evaluated and the microstructures were systematically characterized.Microstructural evolution from millimeter-to nano-scale was explored,with special attention paid to the localized deformation.Microstructural evolution begins with the formation of planar dislocation arrays and the twin-matrix lamellae,which is followed by the localized deformation characterized by the initiation and the development of shear bands.A twinning-dominated process that was supplemented with dislocation slip-dominated one governed the microstructural evolution inside shear bands.The twin-matrix lamellae transform into extended/lamellar structure and finally the nanosized grains.Austenitic grains were substantially refined and martensitic transformation was effectively suppressed,of which the underlying mechanisms were analyzed.展开更多
In order to understand the current interface characteristics of wood-hybrid composites, this paper starts off from the concept of composite interface and general theory of interface form, then the inner-surface and mi...In order to understand the current interface characteristics of wood-hybrid composites, this paper starts off from the concept of composite interface and general theory of interface form, then the inner-surface and microstructure of wood and the interface characteristics of composites, such as wood- inorganic, wood- plastic and wood- metal made by electroless plating technique, are concluded and discussed in detail. Meanwhile, on the basis of that, some points of view about how to develop the wood-hybrid composites interface research in the future are also proposed.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11175030,11175029,91230205,and 11375032)the National High-Tech ICF Committee of China,the National Basic Research Program of China(Grant Nos.2008CB717806 and 2011CB808104)the Science and Technology Foundation of China Academy of Engineering Physics(Grant No.2011A0102008)
文摘The effect of inner-surface roughness of conical targets on the generation of fast electrons in the laser-cone interaction is investigated using particle-in-cell simulation. It is found that the surface roughness can reduce the fast-electron number (in the energy range E 〉 1 MeV) and energy, as compared to that from a cone with smooth inner wall. A scaling law for the laser reflectivity based on the vacuum-heating model is derived. Both theory and simulation indicate that laser reflection increases with the height-to-width ratio of the periodic inner surface structure and approaches that of a smooth cone as this ratio becomes zero.
基金supported financially by the Hundred Outstanding Creative Talents Projects in University of Hebei ProvinceChina, the Project Program of Heavy Machinery Collaborative Innovation Center+1 种基金the Natural Science Foundation of Hebei Province, China (No. E2018203312)the Postdoctoral Science Foundation of Hebei Province, China
文摘In the present investigation, a pipe inner-surface grinding(PISG) technique was developed to fabricate nanostructure in the inner-surface of an austenitic 304 stainless steel pipe. PISG was performed by high speed shearing with hard sphere tips, leading to gradient distribution of strain, strain rate and strain gradient along depth. Nano-austenite with an average boundary spacing of 20 nm was generated, followed by deformation microstructure characterized by shear bands, multi-and uni-directional twins and planar dislocation arrays. Deformation induced grain refinement of austenitic 304 stainless steel with low stacking fault energy(SFE) covering 4–5 order's magnitude of length scales toward nanometer regime was unified.
基金the National Natural Science Foundation of China(Nos.21673039,21573042,21805039,21975044,21971038)the Fujian Provincial Department of Science and Technology(Nos.2018J07001,2019H6012)。
文摘Two novel anionic single-walled metal-organic nanotubes(MONTs),[(CH_(3))_(2)NH_(2)][ln(cdc)(thb)].2DMF.9.5H_(2)O(FJU-105)and[(CH_(3))_(2)NH_(2)][ln(cdc)(H-btc)]-2DMA·11H_(2)O(FJU-106)(H_(2)cdc=9H-carbazole-3,6-dicarboxylic acid,H_(2)thb=2,5-thiophene dicarboxylic acid,H3btc=1,3,5-benzene tricarboxylic acid),are achieved by employing[ln_(6)(cdc)_(6)]^(6+)metalloring cluster with largest diameter as the secondary building blocks(SBUs).The inner surface of FJU-106 is functionalized by uncoordinated-COOH groups of the H-btc linkers,leading to a higher proton conduction than FJU-105.At 70℃,FJU-106 displays the proton conduction performances among MONTs,up to 1.80×10^(-2)S·cm(^-1).And FJU-105 and FJU-106 are the first examples of MONT proton conductors operating at subzero temperature.
基金the financial support of the Hundred Outstanding Creative Talents Projects in Hebei University,Chinathe Project Program of Heavy Machinery Collaborative Innovation Center,Chinathe National Natural Foundation of Hebei Province,China (Grant No. E2018203312)
文摘In the present investigation,an austenitic AISI 304 stainless steel was subjected to high strain rate surface deformation by Pipe Inner-Surface Grinding(PISG)technique.The depth-dependent deformation parameters(strain,strain rate and strain gradient)were evaluated and the microstructures were systematically characterized.Microstructural evolution from millimeter-to nano-scale was explored,with special attention paid to the localized deformation.Microstructural evolution begins with the formation of planar dislocation arrays and the twin-matrix lamellae,which is followed by the localized deformation characterized by the initiation and the development of shear bands.A twinning-dominated process that was supplemented with dislocation slip-dominated one governed the microstructural evolution inside shear bands.The twin-matrix lamellae transform into extended/lamellar structure and finally the nanosized grains.Austenitic grains were substantially refined and martensitic transformation was effectively suppressed,of which the underlying mechanisms were analyzed.
基金Supported by the National Natural Science Foundation of China (Grant No.30070606)
文摘In order to understand the current interface characteristics of wood-hybrid composites, this paper starts off from the concept of composite interface and general theory of interface form, then the inner-surface and microstructure of wood and the interface characteristics of composites, such as wood- inorganic, wood- plastic and wood- metal made by electroless plating technique, are concluded and discussed in detail. Meanwhile, on the basis of that, some points of view about how to develop the wood-hybrid composites interface research in the future are also proposed.