A thermodynamic model has been built up for the interactions between molten Ti alloys and oxide molding materials in the way of decomposition and solution of molding materials, then the influences on the reaction free...A thermodynamic model has been built up for the interactions between molten Ti alloys and oxide molding materials in the way of decomposition and solution of molding materials, then the influences on the reaction free energy changes have been calculated and discussed.展开更多
The electrochemical reduction of Zr^4＋（complex） ions in NaCl-KCl-K2ZrF6 molten salt on Pt electrode was investigated using cyclic voltammetry and square wave voltammetry at 1023 K.Two cathodic reduction peaks relat...The electrochemical reduction of Zr^4＋（complex） ions in NaCl-KCl-K2ZrF6 molten salt on Pt electrode was investigated using cyclic voltammetry and square wave voltammetry at 1023 K.Two cathodic reduction peaks related to Zr^4＋/Zr^2＋ and Zr^2＋/Zr steps were observed in the cyclic voltammograms.The result was also confirmed by square wave voltammetry.The diffusion coefficient of Zr^4＋（complex） ions at 1023 K in NaCl-KCl-K2ZrF6 melt,measured by cyclic voltammetry,is about 4.22×10^-6 cm^2/s.The characterization of the deposits obtained by potentiostatic electrolysis at different potentials was investigated by XRD,and the results were well consistent with the electrochemical reduction mechanism of Zr^4＋（complex） ions.展开更多
The production of Y2O3-ZrO2 powder by the reaction of zirconium salt and yttrium salt, combined in a certain proportion, with sodium nitrate under molten state was described. The effects of adding Cl-, Br- and CO2-3 a...The production of Y2O3-ZrO2 powder by the reaction of zirconium salt and yttrium salt, combined in a certain proportion, with sodium nitrate under molten state was described. The effects of adding Cl-, Br- and CO2-3 anions, as well as introducing ultrasonic vibration during the reaction on the crystallite size of Y2O3-Zr2O3 powder were investigated.展开更多
The electrochemical behaviour of Pr(III) on iron electrode in molten PrCl3-KCl-NaCl was studied by means of cyclic voltammetry and potential-time curve method. The results show that the reduction of Pr(III) to Pr on t...The electrochemical behaviour of Pr(III) on iron electrode in molten PrCl3-KCl-NaCl was studied by means of cyclic voltammetry and potential-time curve method. The results show that the reduction of Pr(III) to Pr on the iron electrode proceeds reversibly in one step and forms Pr-Fe alloys. The Pr-Fe alloys are obtained by molten salt electrolysis with molten KCl-NaCl as electrolyte and PrCl3 as raw materials. The composition of electrolytic product is PrFe2 and Pr analysed by X-ray diffraction. Pr recovery efficiency is 90% and the current efficiency is 85%.展开更多
The erosion resistance properties of O'-Sialon-BN in molten steel are investigated in this work. According to experimental results and theoretical analysis, BN in O'-Sialon-BN plays an important role in the mo...The erosion resistance properties of O'-Sialon-BN in molten steel are investigated in this work. According to experimental results and theoretical analysis, BN in O'-Sialon-BN plays an important role in the molten steel erosion resistance. And the erosion kinetics of the O'-Sialon-BN composites in molten steel is controlled by two stages: the first one is controlled by the chemical reaction taking place on the interface; the second one is controlled by diffusion. The erosion surface of materials is also investigated with fractal theory. The results show that the fractal dimensions of the erosion surface vary with the erosion time from a linear way to a parabolic way, which is related to the erosion mechanism change from interface chemical reaction to diffusion.展开更多
The cyclic voltammetry, electrode potential-time curve after potentiostatic electrolysis, potential-step method and X-ray diffraction were used to study the electrochemical reaction of Dy (III) in NaCl-KCl equimolar m...The cyclic voltammetry, electrode potential-time curve after potentiostatic electrolysis, potential-step method and X-ray diffraction were used to study the electrochemical reaction of Dy (III) in NaCl-KCl equimolar mixture on Ni electrode. The DyNi5 forms at first and then the intermetallic compounds of DyNi containing more Dy form in sequence. The metallic Dy deposits at last. The standard free energy of formation for DyNi5 determined is -125.6 kJ/mol at 973K. The diffusion coefficient of Dy into DyNi5 phase determined is 8×0-10 cm2/s at 1032 K. The diffusion activation energy of Dy atoms in its intermetallic compound is 101.3 kJ/mol at 973K.展开更多
Aluminum production is a high energy consumption process so that maintaining fundamental compositions in balance and optimal conditions are essential.The molten electrolyte and melted aluminum are primary materials an...Aluminum production is a high energy consumption process so that maintaining fundamental compositions in balance and optimal conditions are essential.The molten electrolyte and melted aluminum are primary materials and their boundary needs to be monitored from time to time.An automatic measurement technic is presented in the paper to substitute for the traditional manual measurement work that is dull,poor efficiency and dangerous for operators.The boundary forming mechanism is analyzed,the vertical profile of electric potential is simulated,an automatic instrument is developed to sense the potential distribution,and a strategy is provided to identify the boundary according to the potential curves.Finally,some practical results are compared with manual measurements,which shows good consistency.展开更多
In this study,the effects of changing first wall materials and their thicknesses on a reactor were investigated to determine the displacement per atom(DPA)and gas production(helium and hydrogen)in the first wall,as we...In this study,the effects of changing first wall materials and their thicknesses on a reactor were investigated to determine the displacement per atom(DPA)and gas production(helium and hydrogen)in the first wall,as well as the tritium breeding ratio(TBR)in the coolant and tritium breeding zones.Therefore,the modeling of the magnetic fusion reactor was determined based on the blanket parameters of the International Thermonuclear Experimental Reactor(ITER).Stainless steel(SS 316 LNIG),Oxide Dispersion Strengthened Steel alloy(PM2000 ODS),and China low-activation martensitic steel(CLAM)were used as the first wall(FW)materials.Fluoride family molten salt materials(FLiBe,FLiNaBe,FLiPb)and lithium oxide(LiO_(2))were considered the coolant and tritium production material in the blanket,respectively.Neutron transport calculations were performed using the wellknown 3D code MCNP5 using the continuous-energy Monte Carlo method.The built-in continuous energy nuclear and atomic data libraries along with the Evaluated Nuclear Data file(ENDF)system(ENDF/B-V and ENDF/B-VI)were used.Additionally,the activity cross-section data library CLAW-IV was used to evaluate both the DPA values and gas production of the first wall(FW)materials.An interface computer program written in the FORTRAN 90 language to evaluate the MCNP5 outputs was developed for the fusion reactor blanket.The results indicated that the best TBR value was obtained for the use of the FLiPb coolant,whereas depending on the thickness,the first wall replacement period in terms of radiation damage to all materials was between 6 and 11 years.展开更多
基金This work was supported by Postdoctoral Foundation of Northwestern Polytechnical University and Science Research FOundation o
文摘A thermodynamic model has been built up for the interactions between molten Ti alloys and oxide molding materials in the way of decomposition and solution of molding materials, then the influences on the reaction free energy changes have been calculated and discussed.
文摘The electrochemical reduction of Zr^4＋（complex） ions in NaCl-KCl-K2ZrF6 molten salt on Pt electrode was investigated using cyclic voltammetry and square wave voltammetry at 1023 K.Two cathodic reduction peaks related to Zr^4＋/Zr^2＋ and Zr^2＋/Zr steps were observed in the cyclic voltammograms.The result was also confirmed by square wave voltammetry.The diffusion coefficient of Zr^4＋（complex） ions at 1023 K in NaCl-KCl-K2ZrF6 melt,measured by cyclic voltammetry,is about 4.22×10^-6 cm^2/s.The characterization of the deposits obtained by potentiostatic electrolysis at different potentials was investigated by XRD,and the results were well consistent with the electrochemical reduction mechanism of Zr^4＋（complex） ions.
文摘The production of Y2O3-ZrO2 powder by the reaction of zirconium salt and yttrium salt, combined in a certain proportion, with sodium nitrate under molten state was described. The effects of adding Cl-, Br- and CO2-3 anions, as well as introducing ultrasonic vibration during the reaction on the crystallite size of Y2O3-Zr2O3 powder were investigated.
文摘The electrochemical behaviour of Pr(III) on iron electrode in molten PrCl3-KCl-NaCl was studied by means of cyclic voltammetry and potential-time curve method. The results show that the reduction of Pr(III) to Pr on the iron electrode proceeds reversibly in one step and forms Pr-Fe alloys. The Pr-Fe alloys are obtained by molten salt electrolysis with molten KCl-NaCl as electrolyte and PrCl3 as raw materials. The composition of electrolytic product is PrFe2 and Pr analysed by X-ray diffraction. Pr recovery efficiency is 90% and the current efficiency is 85%.
基金Acknowledgements - This research work is sponsored by the National Natural Science Foundation of China(Grant No.59674028)
文摘The erosion resistance properties of O'-Sialon-BN in molten steel are investigated in this work. According to experimental results and theoretical analysis, BN in O'-Sialon-BN plays an important role in the molten steel erosion resistance. And the erosion kinetics of the O'-Sialon-BN composites in molten steel is controlled by two stages: the first one is controlled by the chemical reaction taking place on the interface; the second one is controlled by diffusion. The erosion surface of materials is also investigated with fractal theory. The results show that the fractal dimensions of the erosion surface vary with the erosion time from a linear way to a parabolic way, which is related to the erosion mechanism change from interface chemical reaction to diffusion.
文摘The cyclic voltammetry, electrode potential-time curve after potentiostatic electrolysis, potential-step method and X-ray diffraction were used to study the electrochemical reaction of Dy (III) in NaCl-KCl equimolar mixture on Ni electrode. The DyNi5 forms at first and then the intermetallic compounds of DyNi containing more Dy form in sequence. The metallic Dy deposits at last. The standard free energy of formation for DyNi5 determined is -125.6 kJ/mol at 973K. The diffusion coefficient of Dy into DyNi5 phase determined is 8×0-10 cm2/s at 1032 K. The diffusion activation energy of Dy atoms in its intermetallic compound is 101.3 kJ/mol at 973K.
文摘Aluminum production is a high energy consumption process so that maintaining fundamental compositions in balance and optimal conditions are essential.The molten electrolyte and melted aluminum are primary materials and their boundary needs to be monitored from time to time.An automatic measurement technic is presented in the paper to substitute for the traditional manual measurement work that is dull,poor efficiency and dangerous for operators.The boundary forming mechanism is analyzed,the vertical profile of electric potential is simulated,an automatic instrument is developed to sense the potential distribution,and a strategy is provided to identify the boundary according to the potential curves.Finally,some practical results are compared with manual measurements,which shows good consistency.
文摘In this study,the effects of changing first wall materials and their thicknesses on a reactor were investigated to determine the displacement per atom(DPA)and gas production(helium and hydrogen)in the first wall,as well as the tritium breeding ratio(TBR)in the coolant and tritium breeding zones.Therefore,the modeling of the magnetic fusion reactor was determined based on the blanket parameters of the International Thermonuclear Experimental Reactor(ITER).Stainless steel(SS 316 LNIG),Oxide Dispersion Strengthened Steel alloy(PM2000 ODS),and China low-activation martensitic steel(CLAM)were used as the first wall(FW)materials.Fluoride family molten salt materials(FLiBe,FLiNaBe,FLiPb)and lithium oxide(LiO_(2))were considered the coolant and tritium production material in the blanket,respectively.Neutron transport calculations were performed using the wellknown 3D code MCNP5 using the continuous-energy Monte Carlo method.The built-in continuous energy nuclear and atomic data libraries along with the Evaluated Nuclear Data file(ENDF)system(ENDF/B-V and ENDF/B-VI)were used.Additionally,the activity cross-section data library CLAW-IV was used to evaluate both the DPA values and gas production of the first wall(FW)materials.An interface computer program written in the FORTRAN 90 language to evaluate the MCNP5 outputs was developed for the fusion reactor blanket.The results indicated that the best TBR value was obtained for the use of the FLiPb coolant,whereas depending on the thickness,the first wall replacement period in terms of radiation damage to all materials was between 6 and 11 years.
