The microstructure,extrusion texture and corrosion behavior of extruded dilute Mg–Al–Ca–Mn alloy with diferent Al contents were investigated.The corrosion rate of the alloy was more sensitive to the Fe impurities.T...The microstructure,extrusion texture and corrosion behavior of extruded dilute Mg–Al–Ca–Mn alloy with diferent Al contents were investigated.The corrosion rate of the alloy was more sensitive to the Fe impurities.The 1.2 wt%Al showed the lowest corrosion rate,which was mainly attributed to the weakening of the cathode efect caused by the increase of the Al and the decrease of the Fe in the precipitated phase.Refned grains,stronger basal surface texture and higher corrosion potential deriving from the higher Al content of the matrix also further enhanced the corrosion resistance of the matrix.展开更多
An analysis has been completed for a comprehensive set of vertical,dilute-phase pneumatic conveying pressure drop data from an investigation by Flatow.The data were collected in the established flow region for eight d...An analysis has been completed for a comprehensive set of vertical,dilute-phase pneumatic conveying pressure drop data from an investigation by Flatow.The data were collected in the established flow region for eight different materials conveyed in 0.05-,0.10-,0.20-m internal diameter,20-m tall steel risers.Particle velocities derived from the pressure drop data were used to develop an equation of motion that includes terms for pipe diameter,terminal velocity,coefficient of restitution,and particle shape.The best data fit was achieved using the actual gas density and the actual gas velocity adjusted for voidage.Adjusting the terminal velocity for voidage,an approach recommended by many investigators,did not improve the fit for reasons identified by the present research.Using the equation of motion,particle velocities were predicted and used to calculate total pressure drops that are within±15%of the measured values.The calculated values also produce the characteristic trough-shaped total pressure drop curves allowing the minimum pressure drop gas velocity to be determined without recourse to a separate correlation.A comparison with other studies using shorter risers indicates that data from these studies likely include acceleration effects.A separate study will investigate this observation further.展开更多
The dilute magnetic intermetallic compound(DMIC) is an extended study of the dilute magnetic semiconductor. The giant magnetic effect and room temperature ferromagnetism are induced by doping minor 3d transition metal...The dilute magnetic intermetallic compound(DMIC) is an extended study of the dilute magnetic semiconductor. The giant magnetic effect and room temperature ferromagnetism are induced by doping minor 3d transition metal into REIn_(3) intermetallic compound. Owing to the metallic processability, the REIn_(3)-based DMIC might have the potential application as magnetoelectric device. In this review, the structural stability, magnetic and electric transport properties of REIn_(3-x)T_(x)(RE = rare earth;T = Co, Mn, Fe;x = 0–0.3) have been systematically summarized and analyzed.展开更多
The present work deals with the computation of the gas-solid two-phase flow pressure drop across thin and thick orifices for a vertically downward flow configuration at the higher limits of a dilute phase flow situati...The present work deals with the computation of the gas-solid two-phase flow pressure drop across thin and thick orifices for a vertically downward flow configuration at the higher limits of a dilute phase flow situation(0.01≤αs,in≤0.10).The Eulerian-Eulerian(two-fluid)model has been used in conjunction with the kinetic theory of granular flow with a four-way coupling approach.The validation of the solution process has been performed by comparing the computational result with the existing experimental data.It is observed that the two-phase flow pressure drop across the orifice increases with an increase in the thickness of the orifice,and the effect is more prominent at higher solid loading.The pressure drop is found to increase with an increase in the solid volume fraction.An increase in the Reynolds number or the area ratio increases the pressure drop.An increase in the size of the particles reduces the pressure drop across the orifice at both small and relatively large solid volume fractions.Finally,a two-phase multiplier has been proposed in terms of the relevant parameters,which can be useful to evaluate the gas-solid two-phase flow pressure drop across the orifice and can subsequently help to improve the system performance.展开更多
基金supported by the National Natural Science Foundation of China(No.51804130)the Key Research and Development Projects of Science and Technology Development Plan of Jilin Province(No.20180201054GX)the Graduate Innovation Fund of Jilin University(Nos.101832020CX241,101832020CX242).
文摘The microstructure,extrusion texture and corrosion behavior of extruded dilute Mg–Al–Ca–Mn alloy with diferent Al contents were investigated.The corrosion rate of the alloy was more sensitive to the Fe impurities.The 1.2 wt%Al showed the lowest corrosion rate,which was mainly attributed to the weakening of the cathode efect caused by the increase of the Al and the decrease of the Fe in the precipitated phase.Refned grains,stronger basal surface texture and higher corrosion potential deriving from the higher Al content of the matrix also further enhanced the corrosion resistance of the matrix.
文摘An analysis has been completed for a comprehensive set of vertical,dilute-phase pneumatic conveying pressure drop data from an investigation by Flatow.The data were collected in the established flow region for eight different materials conveyed in 0.05-,0.10-,0.20-m internal diameter,20-m tall steel risers.Particle velocities derived from the pressure drop data were used to develop an equation of motion that includes terms for pipe diameter,terminal velocity,coefficient of restitution,and particle shape.The best data fit was achieved using the actual gas density and the actual gas velocity adjusted for voidage.Adjusting the terminal velocity for voidage,an approach recommended by many investigators,did not improve the fit for reasons identified by the present research.Using the equation of motion,particle velocities were predicted and used to calculate total pressure drops that are within±15%of the measured values.The calculated values also produce the characteristic trough-shaped total pressure drop curves allowing the minimum pressure drop gas velocity to be determined without recourse to a separate correlation.A comparison with other studies using shorter risers indicates that data from these studies likely include acceleration effects.A separate study will investigate this observation further.
文摘The dilute magnetic intermetallic compound(DMIC) is an extended study of the dilute magnetic semiconductor. The giant magnetic effect and room temperature ferromagnetism are induced by doping minor 3d transition metal into REIn_(3) intermetallic compound. Owing to the metallic processability, the REIn_(3)-based DMIC might have the potential application as magnetoelectric device. In this review, the structural stability, magnetic and electric transport properties of REIn_(3-x)T_(x)(RE = rare earth;T = Co, Mn, Fe;x = 0–0.3) have been systematically summarized and analyzed.
文摘The present work deals with the computation of the gas-solid two-phase flow pressure drop across thin and thick orifices for a vertically downward flow configuration at the higher limits of a dilute phase flow situation(0.01≤αs,in≤0.10).The Eulerian-Eulerian(two-fluid)model has been used in conjunction with the kinetic theory of granular flow with a four-way coupling approach.The validation of the solution process has been performed by comparing the computational result with the existing experimental data.It is observed that the two-phase flow pressure drop across the orifice increases with an increase in the thickness of the orifice,and the effect is more prominent at higher solid loading.The pressure drop is found to increase with an increase in the solid volume fraction.An increase in the Reynolds number or the area ratio increases the pressure drop.An increase in the size of the particles reduces the pressure drop across the orifice at both small and relatively large solid volume fractions.Finally,a two-phase multiplier has been proposed in terms of the relevant parameters,which can be useful to evaluate the gas-solid two-phase flow pressure drop across the orifice and can subsequently help to improve the system performance.
