Microstructural evolution of infrared vacuum brazed CP-Ti using two Ti-based braze alloys,Ti-15Cu-15Ni and Ti-15Cu-25Ni,has been investigated.The infrared brazed joint consisted of eutectic Ti 2 Cu/Ti 2 Ni intermetall...Microstructural evolution of infrared vacuum brazed CP-Ti using two Ti-based braze alloys,Ti-15Cu-15Ni and Ti-15Cu-25Ni,has been investigated.The infrared brazed joint consisted of eutectic Ti 2 Cu/Ti 2 Ni intermetallic compounds and Ti-rich matrix.The eutectic Ti 2 Cu/Ti 2 Ni intermetallic compounds disappeared from the joint after being annealed at 900 C for 1 h.In contrast,the depletion rate of both Cu and Ni from the braze alloy into CP-Ti substrate at 750 C annealing was greatly decreased as compared with that annealed at 900 C.Blocky Ti 2 Cu/Ti 2 Ni phases were observed even if the specimen was annealed at 750 C for 15 h.Because the Ni content of the Ti-15Cu-25Ni braze alloy is much higher than that of the Ti-15Cu-15Ni alloy,the amount of eutectic Ti 2 Cu/Ti 2 Ni phases in Ti-15Cu-25Ni brazed joint is more than that in Ti-15Ci-15Ni brazed joint.However,similar microstructural evolution can be obtained from the infrared brazed joint annealed at various temperatures and/or time for both filler metals.展开更多
In response to the growing environmental threat posed by plastic waste,this study developed hydrophobic biopolymer films from red seaweed(Kappaphycus alvarezii)as a sustainable alternative for packaging.The films were...In response to the growing environmental threat posed by plastic waste,this study developed hydrophobic biopolymer films from red seaweed(Kappaphycus alvarezii)as a sustainable alternative for packaging.The films were fabricated using a solvent-casting method,followed by surface treatment with triethoxymethylsilane to increase their hydrophobicity.Key metrics,including water solubility(reduced by 37.4%),moisture absorption capacity(decreased by 108.6%),and water vapor permeability(decreased by 65.4%),demonstrated significant improvements over untreated films.Fourier transform infrared(FT-IR)spectroscopy confirmed successful silane integration,whereas mechanical testing revealed increased tensile strength(up to 24.44 MPa)and Young’s modulus(183.41 MPa),with a moderate reduction in elongation at break.These findings indicate that silane-modified seaweed biopolymer films have strong potential as eco-friendly packaging solutions to mitigate plastic waste.展开更多
A new predictive computer simulation tool targeting the development of the H-mode pedestal at the plasma edge in tokamaks and the triggering and dynamics of edge localizedmodes(ELMs)is presented in this report.This to...A new predictive computer simulation tool targeting the development of the H-mode pedestal at the plasma edge in tokamaks and the triggering and dynamics of edge localizedmodes(ELMs)is presented in this report.This tool brings together,in a coordinated and effective manner,several first-principles physics simulation codes,stability analysis packages,and data processing and visualization tools.A Kepler workflow is used in order to carry out an edge plasma simulation that loosely couples the kinetic code,XGC0,with an ideal MHD linear stability analysis code,ELITE,and an extended MHD initial value code such as M3D or NIMROD.XGC0 includes the neoclassical ion-electron-neutral dynamics needed to simulate pedestal growth near the separatrix.The Kepler workflow processes the XGC0 simulation results into simple images that can be selected and displayed via the Dashboard,a monitoring tool implemented in AJAX allowing the scientist to track computational resources,examine running and archived jobs,and view key physics data,all within a standard Web browser.The XGC0 simulation is monitored for the conditions needed to trigger an ELM crash by periodically assessing the edge plasma pressure and current density profiles using the ELITE code.If an ELM crash is triggered,the Kepler workflow launches the M3D code on a moderate-size Opteron cluster to simulate the nonlinear ELM crash and to compute the relaxation of plasma profiles after the crash.This process is monitored through periodic outputs of plasma fluid quantities that are automatically visualized with AVS/Express and may be displayed on the Dashboard.Finally,the Kepler workflow archives all data outputs and processed images using HPSS,as well as provenance information about the software and hardware used to create the simulation.The complete process of preparing,executing and monitoring a coupled-code simulation of the edge pressure pedestal buildup and the ELM cycle using the Kepler scientific workflow system is described in this paper.展开更多
基金support of this research by the National Science Council(NSC),Taiwan,China (Grant No.NSC 99-2221-E-002-051)
文摘Microstructural evolution of infrared vacuum brazed CP-Ti using two Ti-based braze alloys,Ti-15Cu-15Ni and Ti-15Cu-25Ni,has been investigated.The infrared brazed joint consisted of eutectic Ti 2 Cu/Ti 2 Ni intermetallic compounds and Ti-rich matrix.The eutectic Ti 2 Cu/Ti 2 Ni intermetallic compounds disappeared from the joint after being annealed at 900 C for 1 h.In contrast,the depletion rate of both Cu and Ni from the braze alloy into CP-Ti substrate at 750 C annealing was greatly decreased as compared with that annealed at 900 C.Blocky Ti 2 Cu/Ti 2 Ni phases were observed even if the specimen was annealed at 750 C for 15 h.Because the Ni content of the Ti-15Cu-25Ni braze alloy is much higher than that of the Ti-15Cu-15Ni alloy,the amount of eutectic Ti 2 Cu/Ti 2 Ni phases in Ti-15Cu-25Ni brazed joint is more than that in Ti-15Ci-15Ni brazed joint.However,similar microstructural evolution can be obtained from the infrared brazed joint annealed at various temperatures and/or time for both filler metals.
文摘In response to the growing environmental threat posed by plastic waste,this study developed hydrophobic biopolymer films from red seaweed(Kappaphycus alvarezii)as a sustainable alternative for packaging.The films were fabricated using a solvent-casting method,followed by surface treatment with triethoxymethylsilane to increase their hydrophobicity.Key metrics,including water solubility(reduced by 37.4%),moisture absorption capacity(decreased by 108.6%),and water vapor permeability(decreased by 65.4%),demonstrated significant improvements over untreated films.Fourier transform infrared(FT-IR)spectroscopy confirmed successful silane integration,whereas mechanical testing revealed increased tensile strength(up to 24.44 MPa)and Young’s modulus(183.41 MPa),with a moderate reduction in elongation at break.These findings indicate that silane-modified seaweed biopolymer films have strong potential as eco-friendly packaging solutions to mitigate plastic waste.
基金This work is part of the ongoing research activities within the SciDAC Fusion Simulation Prototype(FSP)Center for Plasma Edge Simulationwhich is supported by the Office of Fusion Energy Sciences and the Office of Advanced Scientific Computing Research within the U.S.Department of Energy.
文摘A new predictive computer simulation tool targeting the development of the H-mode pedestal at the plasma edge in tokamaks and the triggering and dynamics of edge localizedmodes(ELMs)is presented in this report.This tool brings together,in a coordinated and effective manner,several first-principles physics simulation codes,stability analysis packages,and data processing and visualization tools.A Kepler workflow is used in order to carry out an edge plasma simulation that loosely couples the kinetic code,XGC0,with an ideal MHD linear stability analysis code,ELITE,and an extended MHD initial value code such as M3D or NIMROD.XGC0 includes the neoclassical ion-electron-neutral dynamics needed to simulate pedestal growth near the separatrix.The Kepler workflow processes the XGC0 simulation results into simple images that can be selected and displayed via the Dashboard,a monitoring tool implemented in AJAX allowing the scientist to track computational resources,examine running and archived jobs,and view key physics data,all within a standard Web browser.The XGC0 simulation is monitored for the conditions needed to trigger an ELM crash by periodically assessing the edge plasma pressure and current density profiles using the ELITE code.If an ELM crash is triggered,the Kepler workflow launches the M3D code on a moderate-size Opteron cluster to simulate the nonlinear ELM crash and to compute the relaxation of plasma profiles after the crash.This process is monitored through periodic outputs of plasma fluid quantities that are automatically visualized with AVS/Express and may be displayed on the Dashboard.Finally,the Kepler workflow archives all data outputs and processed images using HPSS,as well as provenance information about the software and hardware used to create the simulation.The complete process of preparing,executing and monitoring a coupled-code simulation of the edge pressure pedestal buildup and the ELM cycle using the Kepler scientific workflow system is described in this paper.
