Palladium nanoparticles(PdNPs)were synthesized in a green way using sodium alginate functioning as both reductant and stabilizer.The formation of as-synthesized Pd NPs was supervised by Ultraviolet–visible(UV–Vis)sp...Palladium nanoparticles(PdNPs)were synthesized in a green way using sodium alginate functioning as both reductant and stabilizer.The formation of as-synthesized Pd NPs was supervised by Ultraviolet–visible(UV–Vis)spectroscopy and confirmed by the surface plasmon resonance(SPR)band.The effect of several synthesis factors such as precursor ratio,solution p H,reaction time,and temperature were investigated by the factorial design of experiments in order to optimize the experimental conditions.The optimal synthesis parameters were achieved by heating 1.0 ml of 1.0%sodium alginate(SA),3.0 ml of 10-2 mol·L-1 H2PdCl4 at 80°C for a period of 30 min in a neutral reaction medium(pH=6).High-resolution transmission electron microscope(HRTEM),energy dispersive X-ray(EDX)spectroscopy,selected area electron diffraction(SAED)pattern,X-ray powder diffraction(XRD),and dynamic light scattering(DLS)were used to confirm the uniform spherical shapes and high crystallinity of Pd NPs with average particle size of(2.12±1.42)nm.The SEM images show the distribution of Pd NPs presented among the SA.FTIR spectra indicate that SA is a good capping agent to stabilize Pd NPs for a long time.The catalytic degradation of model azo-dyes such as mono-azo(Cibacron Yellow FN–2R)and di-azo(Cibacron Deep Red S–B)were confirmed the catalytic activity of Pd NPs.The Pd NPs can accelerate the degradation rate by more than 80 and 10 times respectively as confirmed by kinetics constant(k)values.展开更多
The endoplasmic reticulum(ER)is the most widespread organelle within eukaryotic cells,performing various essential functions such as protein synthesis,post-translational modifications,and lipid metabolism.Abnormal flu...The endoplasmic reticulum(ER)is the most widespread organelle within eukaryotic cells,performing various essential functions such as protein synthesis,post-translational modifications,and lipid metabolism.Abnormal fluctuations of biologically active species and microenvironments in the ER can disrupt homeostasis and eventually lead to ER stress,which is closely linked to the occurrence and progression of many human diseases.Therefore,the ER has been regarded as an important analytical object as well as a promising therapeutic target in both bio sensing and biomedicine.Recently,there has been a growing interest in developing photon-excited molecular tools to uncover the physio pathological roles of ER and treat ERrelated disorders.This review presents a comprehensive summary of recent advances in ER-targeted small-molecule probes and their applications for fluorescent sensing and phototherapy,mainly focusing on targeting strategies and probe design principles.Last,we discuss the challenges involved with ER-targeted probes and highlight potential prospects in this field.展开更多
Ti-6Al-4V alloy(Ti64)and SUS316 L stainless steel rods were dissimilarly friction welded.Especially focusing on the detailed observation of interface microstructural evolution during the friction welding(FW),the relat...Ti-6Al-4V alloy(Ti64)and SUS316 L stainless steel rods were dissimilarly friction welded.Especially focusing on the detailed observation of interface microstructural evolution during the friction welding(FW),the relationship between the processing conditions,weld interface microstructure,and mechanical properties of the obtained joints were systematically investigated to elucidate the principle for obtaining a high joint quality in the FW of Ti64 and SUS316L.A higher friction pressure produced a lower welding temperature in the FW,hence suppressing the thick intermetallic compound layer formation.However,hard and brittle Ti64/SUS316L mechanically mixed layers generally formed especially at the weld interface periphery due to the high temperature increasing rate,high rotation linear velocity and high outward flow velocity of the Ti64.These harmful layers tended to induce the cracks/voids formation at the weld interfaces hence deteriorating the joints’mechanical properties.The rotation speed reduction and liquid CO2 cooling during the entire processing decreased the temperature increasing rate,rotation linear velocity and outward flow velocity of the Ti64 at the weld interface periphery.Therefore,they suppressed the formation of the harmful mechanically mixed layers,facilitated the homogeneous and sound interface microstructure generation,and finally produced a high-quality dissimilar joint in the FW of Ti64 and SUS316L.展开更多
The Al alloy and carbon fiber reinforced polymer(CFRP)hybrid structures,incorporating the performance advantages of the two materials,have been attracting more attention in high-end manufacturing fields.In the current...The Al alloy and carbon fiber reinforced polymer(CFRP)hybrid structures,incorporating the performance advantages of the two materials,have been attracting more attention in high-end manufacturing fields.In the current investigation,the flat friction spot joining(FSJ)was employed in joining the AA6061-T6 alloy and CFRP sheets.The significance of temperature distribution in influencing joint quality was highlighted through analyzing interface microstructural features,weld defect formation as well as fractography.To understand the role of thermal energy generation and conduction in the process comprehensively,a 3D thermal-mechanical coupling finite element model was established.The interfacial temperature was characterized by an uneven distribution behavior due to the inhomogeneous heat distribution.The peak temperatures on the top surface and Al alloy to CFRP interface at 1500 rpm rotational speed with 0.1 mm/s plunging speed were 498℃and 489°C,respectively.The peak interface temperature was reduced to286℃at 250 rpm,which produced an extremely small melted area.Compared with the plunging speed,rotational speed was found to be the predominant parameter for determining the joint property,which could be optimized to simultaneously realize the avoidance of thermal decomposition of CFRP,the sufficient melting duration time,and the wide enough melted area.Simulated thermal histories and melted area profiles were in agreement with experimental ones.The findings could be utilized to provide some feasible guidance for process optimization of dissimilar FSJ of metals and composites.展开更多
Friction self-piercing riveting(F-SPR)is an emerging technique for low ductility materials joining,which creates a mechanical and solid-state hybrid joint with a semi-hollow rivet.The severe plastic deformation of wor...Friction self-piercing riveting(F-SPR)is an emerging technique for low ductility materials joining,which creates a mechanical and solid-state hybrid joint with a semi-hollow rivet.The severe plastic deformation of work materials and localized elevated temperatures during the F-SPR process yield complex and heterogeneous microstructures.The cut-off action of the work materials by the rivet further complicates the material flow during joint formation.This study employed the F-SPR process to join AA7075-T6 aluminum alloy sheets and systematically investigated the microstructural evolutions using electron backscatter diffraction(EBSD)techniques.The results suggested that as the base material approached the rivet,grains were deformed and recrystallized,forming two distinct fine grain zones(FGZs)surrounding the rivet and in the rivet cavity,re s pectively.Solid-state bonding of aluminum sheets occurred in the FGZs.The formation of FGZ outside the rivet is due to dynamic recrystallization(DRX)triggered by the sliding-to-sticking transition at the rivet/sheet interface.The FGZ in the rivet cavity was caused by the rotation of the trapped aluminum,which created a sticking affected zone at the trapped aluminum/lower sheet interface and led to DRX.Strain rate gradient in the trapped aluminum drove the further expansion of the sticking affected zone and resulted in grain refinement in a larger span.展开更多
基金the kind support of this work from Key Laboratory of Biomass Fibers&Eco-Dyeing&Finishing,Hubei Province(STRZ2019015)the Innovation Platform Projects of Wuhan Textile University(183052)。
文摘Palladium nanoparticles(PdNPs)were synthesized in a green way using sodium alginate functioning as both reductant and stabilizer.The formation of as-synthesized Pd NPs was supervised by Ultraviolet–visible(UV–Vis)spectroscopy and confirmed by the surface plasmon resonance(SPR)band.The effect of several synthesis factors such as precursor ratio,solution p H,reaction time,and temperature were investigated by the factorial design of experiments in order to optimize the experimental conditions.The optimal synthesis parameters were achieved by heating 1.0 ml of 1.0%sodium alginate(SA),3.0 ml of 10-2 mol·L-1 H2PdCl4 at 80°C for a period of 30 min in a neutral reaction medium(pH=6).High-resolution transmission electron microscope(HRTEM),energy dispersive X-ray(EDX)spectroscopy,selected area electron diffraction(SAED)pattern,X-ray powder diffraction(XRD),and dynamic light scattering(DLS)were used to confirm the uniform spherical shapes and high crystallinity of Pd NPs with average particle size of(2.12±1.42)nm.The SEM images show the distribution of Pd NPs presented among the SA.FTIR spectra indicate that SA is a good capping agent to stabilize Pd NPs for a long time.The catalytic degradation of model azo-dyes such as mono-azo(Cibacron Yellow FN–2R)and di-azo(Cibacron Deep Red S–B)were confirmed the catalytic activity of Pd NPs.The Pd NPs can accelerate the degradation rate by more than 80 and 10 times respectively as confirmed by kinetics constant(k)values.
基金financial support from the National Natural Science Foundation of China(21974013)Hunan Graduate Research and Innovation Project(CX20210814)+1 种基金Open Research Fund of School of Chemistry and Chemical Engineering,Henan Normal University(2022A04)National Students’Platform for Innovation and Entrepreneurship Training Program(202210542049)
文摘The endoplasmic reticulum(ER)is the most widespread organelle within eukaryotic cells,performing various essential functions such as protein synthesis,post-translational modifications,and lipid metabolism.Abnormal fluctuations of biologically active species and microenvironments in the ER can disrupt homeostasis and eventually lead to ER stress,which is closely linked to the occurrence and progression of many human diseases.Therefore,the ER has been regarded as an important analytical object as well as a promising therapeutic target in both bio sensing and biomedicine.Recently,there has been a growing interest in developing photon-excited molecular tools to uncover the physio pathological roles of ER and treat ERrelated disorders.This review presents a comprehensive summary of recent advances in ER-targeted small-molecule probes and their applications for fluorescent sensing and phototherapy,mainly focusing on targeting strategies and probe design principles.Last,we discuss the challenges involved with ER-targeted probes and highlight potential prospects in this field.
基金the New Energy and Industrial Technology Development Organization(NEDO)under the“Innovation Structural Materials Project(Future Pioneering Projects)”JSPS KAKENHI Grant Numbers JP19H00826 and JP18K14027an ISIJ Research Promotion Grant。
文摘Ti-6Al-4V alloy(Ti64)and SUS316 L stainless steel rods were dissimilarly friction welded.Especially focusing on the detailed observation of interface microstructural evolution during the friction welding(FW),the relationship between the processing conditions,weld interface microstructure,and mechanical properties of the obtained joints were systematically investigated to elucidate the principle for obtaining a high joint quality in the FW of Ti64 and SUS316L.A higher friction pressure produced a lower welding temperature in the FW,hence suppressing the thick intermetallic compound layer formation.However,hard and brittle Ti64/SUS316L mechanically mixed layers generally formed especially at the weld interface periphery due to the high temperature increasing rate,high rotation linear velocity and high outward flow velocity of the Ti64.These harmful layers tended to induce the cracks/voids formation at the weld interfaces hence deteriorating the joints’mechanical properties.The rotation speed reduction and liquid CO2 cooling during the entire processing decreased the temperature increasing rate,rotation linear velocity and outward flow velocity of the Ti64 at the weld interface periphery.Therefore,they suppressed the formation of the harmful mechanically mixed layers,facilitated the homogeneous and sound interface microstructure generation,and finally produced a high-quality dissimilar joint in the FW of Ti64 and SUS316L.
基金financially supported by the New Energy and Industrial Technology Development Organization(NEDO)under the"Innovation Structural Materials Project(Future Pioneering Projects)"。
文摘The Al alloy and carbon fiber reinforced polymer(CFRP)hybrid structures,incorporating the performance advantages of the two materials,have been attracting more attention in high-end manufacturing fields.In the current investigation,the flat friction spot joining(FSJ)was employed in joining the AA6061-T6 alloy and CFRP sheets.The significance of temperature distribution in influencing joint quality was highlighted through analyzing interface microstructural features,weld defect formation as well as fractography.To understand the role of thermal energy generation and conduction in the process comprehensively,a 3D thermal-mechanical coupling finite element model was established.The interfacial temperature was characterized by an uneven distribution behavior due to the inhomogeneous heat distribution.The peak temperatures on the top surface and Al alloy to CFRP interface at 1500 rpm rotational speed with 0.1 mm/s plunging speed were 498℃and 489°C,respectively.The peak interface temperature was reduced to286℃at 250 rpm,which produced an extremely small melted area.Compared with the plunging speed,rotational speed was found to be the predominant parameter for determining the joint property,which could be optimized to simultaneously realize the avoidance of thermal decomposition of CFRP,the sufficient melting duration time,and the wide enough melted area.Simulated thermal histories and melted area profiles were in agreement with experimental ones.The findings could be utilized to provide some feasible guidance for process optimization of dissimilar FSJ of metals and composites.
基金financial support of the National Natural Science Foundation of China(Grant Nos.52025058 and U1764251)the National Key Research and Development Program of China(Grant No.2016YFB0101606-08)+1 种基金Shanghai Jiao Tong Universityfinancially supported by Project to Create Research and Educational Hubs for Innovative Manufacturing in Asia,Joining and Welding Research Institute,Osaka University。
文摘Friction self-piercing riveting(F-SPR)is an emerging technique for low ductility materials joining,which creates a mechanical and solid-state hybrid joint with a semi-hollow rivet.The severe plastic deformation of work materials and localized elevated temperatures during the F-SPR process yield complex and heterogeneous microstructures.The cut-off action of the work materials by the rivet further complicates the material flow during joint formation.This study employed the F-SPR process to join AA7075-T6 aluminum alloy sheets and systematically investigated the microstructural evolutions using electron backscatter diffraction(EBSD)techniques.The results suggested that as the base material approached the rivet,grains were deformed and recrystallized,forming two distinct fine grain zones(FGZs)surrounding the rivet and in the rivet cavity,re s pectively.Solid-state bonding of aluminum sheets occurred in the FGZs.The formation of FGZ outside the rivet is due to dynamic recrystallization(DRX)triggered by the sliding-to-sticking transition at the rivet/sheet interface.The FGZ in the rivet cavity was caused by the rotation of the trapped aluminum,which created a sticking affected zone at the trapped aluminum/lower sheet interface and led to DRX.Strain rate gradient in the trapped aluminum drove the further expansion of the sticking affected zone and resulted in grain refinement in a larger span.
