Emf technique was employed to determine indium activities in the liquid Ag-In-Pd alloys using galvanic cells with yttria-stabilised-zirconia as solid electrolyte according to the scheme： kanthal/rhenium, Ag-In-Pd, In...Emf technique was employed to determine indium activities in the liquid Ag-In-Pd alloys using galvanic cells with yttria-stabilised-zirconia as solid electrolyte according to the scheme： kanthal/rhenium, Ag-In-Pd, In2O3 ｜ YSZ ｜ Ni, NiO, Pt. Composition and temperature measurement ranges were limited, because of very steep liquidus surface; 35 compositions for Xpd up to 0.3 were investigated and at temperatures from near-liquidus up to 1700 K. High temperature experiments required special moly furnace to be constructed with unique automatic gas supply system for fumace winding protective atmosphere. Emf readings were taken and recorded by automatic data acquisition system. Linear dependence of emf on temperature was observed for all compositions investigated, and results were approximated by straight line equa- tions. Then In activities were calculated using well-known relations and taking into account correction for thermoelectric power between kanthal and platinum. Results are to be used along with other existing data to perform assessment of the ternary system under accord.展开更多
The nano powders of LaCrO3 were prepared by a sol-gel route. The heat capacity of LaCrO3 nano powders from 350 to 550 K was measured by DSC method and expressed as： Cpa2CrO3） （±0.112） = 166.844 - 8.500 ×...The nano powders of LaCrO3 were prepared by a sol-gel route. The heat capacity of LaCrO3 nano powders from 350 to 550 K was measured by DSC method and expressed as： Cpa2CrO3） （±0.112） = 166.844 - 8.500 ×10^-3T- 1.022×10^6T^-2 （J/（mol.K）） （350-550 K）. An EMF measurement assembly was developed with CaF2 as an electrolyte for the galvanic cell. From measured EMF data of the reversible cell, （-） PL La2O3, LaF3, O2 （1 atm）lCaF2O2（1 atm）, LaF3, LaCrO3, Cr2O3, Pt（＋）, and the relevant value of Gibbs free energy, the Gibbs free energy of formation of LaCrO3 was calculated from 700 to 885 K： △G ФaLaCrO3 = -1555.364 ＋ 0.354T （kJ/mol） （700-885 K）. And the Gibbs free energy change of reaction from simple oxides La2O3 and Cr2O3 was calculated to be： AG f Oox（LaCrO3） = -94.758 ＋ 8.530×10^-2T（kJ/mol） （700-885 K）.展开更多
基金This work contributes to Group Project No. 4, within the frame of European Project COST "Action 531: Lead-free sol-ders". Financial support from Polish State Committee for Scientific Research under grant No. 62/E - 88/SPB/COST/ T08//DZ 459/2003-2006 is gratefully acknowledged.
文摘Emf technique was employed to determine indium activities in the liquid Ag-In-Pd alloys using galvanic cells with yttria-stabilised-zirconia as solid electrolyte according to the scheme： kanthal/rhenium, Ag-In-Pd, In2O3 ｜ YSZ ｜ Ni, NiO, Pt. Composition and temperature measurement ranges were limited, because of very steep liquidus surface; 35 compositions for Xpd up to 0.3 were investigated and at temperatures from near-liquidus up to 1700 K. High temperature experiments required special moly furnace to be constructed with unique automatic gas supply system for fumace winding protective atmosphere. Emf readings were taken and recorded by automatic data acquisition system. Linear dependence of emf on temperature was observed for all compositions investigated, and results were approximated by straight line equa- tions. Then In activities were calculated using well-known relations and taking into account correction for thermoelectric power between kanthal and platinum. Results are to be used along with other existing data to perform assessment of the ternary system under accord.
基金This project is financially supported by the National Natural Science Foundation of China (Nos. 50374009, 20331030, and 20571009)
文摘The nano powders of LaCrO3 were prepared by a sol-gel route. The heat capacity of LaCrO3 nano powders from 350 to 550 K was measured by DSC method and expressed as： Cpa2CrO3） （±0.112） = 166.844 - 8.500 ×10^-3T- 1.022×10^6T^-2 （J/（mol.K）） （350-550 K）. An EMF measurement assembly was developed with CaF2 as an electrolyte for the galvanic cell. From measured EMF data of the reversible cell, （-） PL La2O3, LaF3, O2 （1 atm）lCaF2O2（1 atm）, LaF3, LaCrO3, Cr2O3, Pt（＋）, and the relevant value of Gibbs free energy, the Gibbs free energy of formation of LaCrO3 was calculated from 700 to 885 K： △G ФaLaCrO3 = -1555.364 ＋ 0.354T （kJ/mol） （700-885 K）. And the Gibbs free energy change of reaction from simple oxides La2O3 and Cr2O3 was calculated to be： AG f Oox（LaCrO3） = -94.758 ＋ 8.530×10^-2T（kJ/mol） （700-885 K）.
