The fatigue performance of a workpiece depends on its surface quality.In traditional fatigue life prediction,the effect of surface quality is commonly accounted for by using empirical correction factors,which is impre...The fatigue performance of a workpiece depends on its surface quality.In traditional fatigue life prediction,the effect of surface quality is commonly accounted for by using empirical correction factors,which is imprecise when safety is of great concern.For surface quality,the surface topography is an important parameter,which introduces stress concentration that reduces the fatigue life.It is not feasible to test the stress concentration of different surface topographies.On the one hand,it is time-consuming and high-cost,and on the other hand,it cannot reflect the general statistical characteristics.With the help of surface reconstruction technology and interpolation method,a more efficient and economic approach is proposed,where FE simulation of workpiece with the reconstructed surface topography is used as a foundation for fatigue life prediction.The relationship between surface roughness(Sa)and fatigue life of the workpiece is studied with the proposed approach.展开更多
The cooperative effect of laser surface texturing(LST) and double glow plasma surface alloying on tribological performance of lubricated sliding contacts was investigated.A Nd:YAG laser was used to generate microdimpl...The cooperative effect of laser surface texturing(LST) and double glow plasma surface alloying on tribological performance of lubricated sliding contacts was investigated.A Nd:YAG laser was used to generate microdimples on steel surfaces. Dimples with the diameter of 150μm and the depth of 30-35μm distributed circumferentially on the disc surface.The alloying element Cr was sputtered to the laser texturing steel surface by double glow plasma technique.A deep diffusion layer with a thickness of 30μm and a high hardness of HV900 was formed in this alloy.Tribological experiments of three types of samples(smooth,texturing and texturing+alloying) were conducted with a ring-on-disc tribometer to simulate the face seal.It is found that,in comparison with smooth steel surfaces,the laser texturing samples significantly reduce the friction coefficient.Moreover,the lower wear rate of the sample treated with the two surface techniques is observed.展开更多
To improve the safety of HMX,HMX/NH_(2)-GO composite was prepared with aqueous ammonia functionalized graphene oxide(NH_(2)-GO).The composite was characterized by SEM,Zeta potential,XPS,Raman spectrum,XRD,HPLC,DSC and...To improve the safety of HMX,HMX/NH_(2)-GO composite was prepared with aqueous ammonia functionalized graphene oxide(NH_(2)-GO).The composite was characterized by SEM,Zeta potential,XPS,Raman spectrum,XRD,HPLC,DSC and BAM sensitivity test.The results indicated that the functionalization with aqueous ammonia can enhance the interaction between GO and HMX,and more efficiently desensitize the explosive.The optimal impact sensitivity of the HMX/NH_(2)-GO composite can be not less than 40 J,which is also the most insensitivity compared to the previous reports prepared by coating desensitization with non-energetic desensitized material.Moreover,the potential reason for the different impact and friction sensitivity was also discussed,which may bring a novel perspective to achieve the desensitization of energetic material.展开更多
Goose parvovirus(GPV)can cause a highly contagious and fatal gosling plague(GP)disease in goslings and muscoy ducklings.Here,three goose-origin neutralizing single chain variable fragment(scFv)antibodies against GPV S...Goose parvovirus(GPV)can cause a highly contagious and fatal gosling plague(GP)disease in goslings and muscoy ducklings.Here,three goose-origin neutralizing single chain variable fragment(scFv)antibodies against GPV SYG-61 were isolated.The genes of scFv antibodies were derived from goslings immunized with GPV SYG-61,and scFvs were subcloned into a pBSD vector for the construction of pBSD-scFv libraries.The pBSD-scFv libraries were screened following three rounds using VP2(protective antigen of GPV)as the bait by flow cytometry(FCM).After screening,the 15 clones with high mean fluorescence intensity(MFI)were isolated and sequenced.These 15 scFvs were expressed by pET-28a(+)in E.coli.The specificity and affinity of the 15 purified scFvs were successfully confirmed by ELISA.In the preliminary neutralization experiment on primary goose embryo fibroblast(GEF)in vitro,three of the 15 purified scFvs(named scFv-10,scFv-11 and scFv-50)showed significant neutralizing capacities.The study generated the first goose-origin neutralizing scFv against GPV and laid the foundation for the appearance of full-length goose-origin neutralizing monoclonal antibody against GPV.展开更多
基金Projects(51535012,U1604255)supported by the National Natural Science Foundation of ChinaProject(2016JC2001)supported by the Key Research and Development Project of Hunan Province,China
文摘The fatigue performance of a workpiece depends on its surface quality.In traditional fatigue life prediction,the effect of surface quality is commonly accounted for by using empirical correction factors,which is imprecise when safety is of great concern.For surface quality,the surface topography is an important parameter,which introduces stress concentration that reduces the fatigue life.It is not feasible to test the stress concentration of different surface topographies.On the one hand,it is time-consuming and high-cost,and on the other hand,it cannot reflect the general statistical characteristics.With the help of surface reconstruction technology and interpolation method,a more efficient and economic approach is proposed,where FE simulation of workpiece with the reconstructed surface topography is used as a foundation for fatigue life prediction.The relationship between surface roughness(Sa)and fatigue life of the workpiece is studied with the proposed approach.
基金Project(2007046) supported by High Technology Research Project of Jiangsu Province,China
文摘The cooperative effect of laser surface texturing(LST) and double glow plasma surface alloying on tribological performance of lubricated sliding contacts was investigated.A Nd:YAG laser was used to generate microdimples on steel surfaces. Dimples with the diameter of 150μm and the depth of 30-35μm distributed circumferentially on the disc surface.The alloying element Cr was sputtered to the laser texturing steel surface by double glow plasma technique.A deep diffusion layer with a thickness of 30μm and a high hardness of HV900 was formed in this alloy.Tribological experiments of three types of samples(smooth,texturing and texturing+alloying) were conducted with a ring-on-disc tribometer to simulate the face seal.It is found that,in comparison with smooth steel surfaces,the laser texturing samples significantly reduce the friction coefficient.Moreover,the lower wear rate of the sample treated with the two surface techniques is observed.
基金the National Natural Science Foundation of China(No.51972278)the Natural Science Foundation of Southwest University of Science and Technology(No.18zx7138)the Project of State Key Laboratory of Environment-friendly Energy Materials,Southwest University of Science and Technology(project no.20fksy16).
文摘To improve the safety of HMX,HMX/NH_(2)-GO composite was prepared with aqueous ammonia functionalized graphene oxide(NH_(2)-GO).The composite was characterized by SEM,Zeta potential,XPS,Raman spectrum,XRD,HPLC,DSC and BAM sensitivity test.The results indicated that the functionalization with aqueous ammonia can enhance the interaction between GO and HMX,and more efficiently desensitize the explosive.The optimal impact sensitivity of the HMX/NH_(2)-GO composite can be not less than 40 J,which is also the most insensitivity compared to the previous reports prepared by coating desensitization with non-energetic desensitized material.Moreover,the potential reason for the different impact and friction sensitivity was also discussed,which may bring a novel perspective to achieve the desensitization of energetic material.
基金Supported by the National Key R&D Program of China(2017YFD0501102,20I7YFD050I103-03 and 2017YFD0501004)Science and Technology Department of Heilongjiang Province(GX18B018)Education Department ofHeilongjiang Province(TSTAU-R2018017)。
文摘Goose parvovirus(GPV)can cause a highly contagious and fatal gosling plague(GP)disease in goslings and muscoy ducklings.Here,three goose-origin neutralizing single chain variable fragment(scFv)antibodies against GPV SYG-61 were isolated.The genes of scFv antibodies were derived from goslings immunized with GPV SYG-61,and scFvs were subcloned into a pBSD vector for the construction of pBSD-scFv libraries.The pBSD-scFv libraries were screened following three rounds using VP2(protective antigen of GPV)as the bait by flow cytometry(FCM).After screening,the 15 clones with high mean fluorescence intensity(MFI)were isolated and sequenced.These 15 scFvs were expressed by pET-28a(+)in E.coli.The specificity and affinity of the 15 purified scFvs were successfully confirmed by ELISA.In the preliminary neutralization experiment on primary goose embryo fibroblast(GEF)in vitro,three of the 15 purified scFvs(named scFv-10,scFv-11 and scFv-50)showed significant neutralizing capacities.The study generated the first goose-origin neutralizing scFv against GPV and laid the foundation for the appearance of full-length goose-origin neutralizing monoclonal antibody against GPV.
