A β”/β-Al_2O_3 solid electrolyte was prepared and used in a Na conentration galvanic cell: (-)O_2(in Ar),SnO_2,Na_2SnO_3|β"/β-Al_2O_3]NaCrO_2,Cr_2O_3,O_2(in Ar)(+).The emf measurements were carried out in te...A β”/β-Al_2O_3 solid electrolyte was prepared and used in a Na conentration galvanic cell: (-)O_2(in Ar),SnO_2,Na_2SnO_3|β"/β-Al_2O_3]NaCrO_2,Cr_2O_3,O_2(in Ar)(+).The emf measurements were carried out in temperature range of 912—1223 K:E=652.1— 0.2092 T+2.3(mV).Using this equation and cited free energies of formation of NaCrO_2, Cr_2O_3 and SnO_2,the molar free energy of formation of Na_2 SnO_3 may be calculated by ΔG°=-1050+0.2544 T±5.4(kJ mol^(-1)).展开更多
The standard Gibbs free energy of formation of magnesium ferrite was determined by means of two types of solid state electrochemical cells: one using MgZr4(PO4)6 (MZP) as the solid electrolyte and the other using...The standard Gibbs free energy of formation of magnesium ferrite was determined by means of two types of solid state electrochemical cells: one using MgZr4(PO4)6 (MZP) as the solid electrolyte and the other using CaF2 as the solid electrolyte. The first cell was operated in the range of 950 to 1100 K. The second cell was operated in the range of 1125 to 1200 K. The reversibility of the cell EMFs was confirmed by microcoulometric titration. The Gibbs energy changes of magnesium ferrite relative to component oxides were calculated based on EMF measurements and are given by following expressions, respectively: AG1 = -3579-15 T (J/mol) and AGⅡ =6258-24.3 T (J/mol). The results obtained from two different cells are consistent with each other. The results also are in agreement with Rao' s and Tretjakov's data in the measured temperature range. When the Gibbs free energies of formation of MgO and Fe203 were substituted in the reaction, the Gibbs free energies of formation of MgFe204 was obtained in two temperature ranges and the for mations are shown as follows: AG 1Formation =-1427394+360.5 T (J/mol) and AGⅡ Formition =-1417557+351.2 T (J/mol).展开更多
The electrochemical formation processes of holmium-cobalt alloys on cobaltcathode in molten HoCl_3-KCl were investigated by cyclic voltammetry and open current potential-timecurve alter potentiostatic electrolysis. Th...The electrochemical formation processes of holmium-cobalt alloys on cobaltcathode in molten HoCl_3-KCl were investigated by cyclic voltammetry and open current potential-timecurve alter potentiostatic electrolysis. The structure of Ho-Co alloys' films deposited on cobaltelectrode by potentiostatic electrolysis was characterized by X-ray diffraction. The standard Gibbsfree energies of formation for the intermetallic compounds of Ho and Co were determined. Thediffusion coefficient and diffusion activation energy of Ho atom in the alloy phase were calculatedto be 10^(-10) -10^(-11) cm^2/s and 96.0 kJ/mol, respectively, from the current-time curve atpotential step.展开更多
The electrochemical alloying of Y-Cu system in molten NaCl-KCl-YCl_3 has been investi- gated.The free energy changes of the formation reactions of the intermetallic compounds,in- cluding YCu_6 ,YCu_4 YCu_2 ,Yfu(973—1...The electrochemical alloying of Y-Cu system in molten NaCl-KCl-YCl_3 has been investi- gated.The free energy changes of the formation reactions of the intermetallic compounds,in- cluding YCu_6 ,YCu_4 YCu_2 ,Yfu(973—103 K),were determined by means of electrode potential-time curves of the working electrode after potentiostatic electrolysis.The results in- dicate that the potential-time method is simple and reliable.展开更多
In this paper it has theoretically proved that the relationship of the molar atomic standard free energies of formation of binary intermediate compounds to the molar fraction of component is a quasi-parabola which is ...In this paper it has theoretically proved that the relationship of the molar atomic standard free energies of formation of binary intermediate compounds to the molar fraction of component is a quasi-parabola which is called a quasi-parabolic regula- tion.展开更多
The iso-activity of[Ce]of samples reached in multiple-hole-graphite crucibles by controlling the oxygen potential through the reaction 2[Ce]+3CO=Ce_(2)O_(3)+3C.Combining conjugate gradient method of solving ill-condit...The iso-activity of[Ce]of samples reached in multiple-hole-graphite crucibles by controlling the oxygen potential through the reaction 2[Ce]+3CO=Ce_(2)O_(3)+3C.Combining conjugate gradient method of solving ill-conditioned equations,the activity interaction coeffients between Ce and Al.Si,Ti and Fe alloying elements were determined.The equilibrium constant of the reaction 2[Ce]+3[O]=Ce_(2)O_(3)and the standard free energy of formation of Ce203 in liquid Cu were obtained at 1.200 C.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
The cyclic voltammetry, open current potential-time curve after potentiostatic electrolysis, the currenttime curve at potential step, XRD, EDAX and EPMA were used to study the electrode process of Ho3+ reduction on n...The cyclic voltammetry, open current potential-time curve after potentiostatic electrolysis, the currenttime curve at potential step, XRD, EDAX and EPMA were used to study the electrode process of Ho3+ reduction on nickel electrode in molten KCI-HoC13 and the phases of surface alloy layer. The Ho-Ni alloys were deposited when Hos+ was reduced on the nickel electrode. The free energies of formation for the intermetallic compounds between Ho and Ni, the diffusion coefficients and diffusion activation energy of Ho astom in the alloy phase were determined.展开更多
The compounds of RESF. RE = La. Ce. Pr, Y and Tb, were made from RE_2S_3 and REF_3 by high tem-perature solid reaction. The Gibbs standard free energies of formation of RESF were measured by galvaniccell technique by ...The compounds of RESF. RE = La. Ce. Pr, Y and Tb, were made from RE_2S_3 and REF_3 by high tem-perature solid reaction. The Gibbs standard free energies of formation of RESF were measured by galvaniccell technique by using CSZ as solid electrolyte. The results of this work together with the Gibbs standardfree energies of formation ol RE,S. . REzSa and REFa were used to determine the phase diagrams ofRESF systems in this paper.展开更多
The combustion energy has been determined for the nine solid complexes of rare earth perchlorate with glycine and imidazole using a rotatingbomb calorimeter.The standard enthalpy of combustion,H0 -c,coor(s), and stan...The combustion energy has been determined for the nine solid complexes of rare earth perchlorate with glycine and imidazole using a rotatingbomb calorimeter.The standard enthalpy of combustion,H0 -c,coor(s), and standard enthalpy of formation,H0 -f,coor(s), for these complexes have been calculated. From the plot of standard enthalpy of formation versus atomic number of the elements in lanthanide series the tripartite effect regularity was observed and the unknown standard enthalpy of formation for similar complexes,Ce(Gly)4(Im)(ClO4)32H2O and Pm(Gly)4(Im)(ClO4)32H2O,can be estimated according to the figure.展开更多
Based on the full optimized molecular geometric structure at 6-311++G** level,the density(ρ),detonation velocity(D),and detonation pressure(P) for a new furazan-based energetic macrocycle compound,hexakis[1...Based on the full optimized molecular geometric structure at 6-311++G** level,the density(ρ),detonation velocity(D),and detonation pressure(P) for a new furazan-based energetic macrocycle compound,hexakis[1,2,5]oxadi-azole[3,4-c:3',4'-e;3'',4''-g:3''',4'''-k:3'''',4''''-m:3''''',4'''''-o][1,2,9,10]-tetraazacyclohexadecine,were investigated to verify its capacity as high energy density material(HEDM). The infrared spectrum was also predicted. The heat of formation(HOF) was calculated using designed isodesmic reaction. The calculation on the bond dissociation energies(BDEs) was done and the pyrolysis mechanism of the compound was studied. The result shows that the N3–O1 bond in the ring may be the weakest one and the ring cleavage is possible to happen in thermal decomposition. The condensed phase HOF and the crystal density were also calculated for the title compound. The detonation data show that it can be considered as a potential HEDM. These results would provide basic information for the molecular design of novel high energy materials.展开更多
文摘A β”/β-Al_2O_3 solid electrolyte was prepared and used in a Na conentration galvanic cell: (-)O_2(in Ar),SnO_2,Na_2SnO_3|β"/β-Al_2O_3]NaCrO_2,Cr_2O_3,O_2(in Ar)(+).The emf measurements were carried out in temperature range of 912—1223 K:E=652.1— 0.2092 T+2.3(mV).Using this equation and cited free energies of formation of NaCrO_2, Cr_2O_3 and SnO_2,the molar free energy of formation of Na_2 SnO_3 may be calculated by ΔG°=-1050+0.2544 T±5.4(kJ mol^(-1)).
基金the National Natural Science Foundation of China (No.50572024) the Education Ministry Foundation for Returning Overseas Scholar of China.
文摘The standard Gibbs free energy of formation of magnesium ferrite was determined by means of two types of solid state electrochemical cells: one using MgZr4(PO4)6 (MZP) as the solid electrolyte and the other using CaF2 as the solid electrolyte. The first cell was operated in the range of 950 to 1100 K. The second cell was operated in the range of 1125 to 1200 K. The reversibility of the cell EMFs was confirmed by microcoulometric titration. The Gibbs energy changes of magnesium ferrite relative to component oxides were calculated based on EMF measurements and are given by following expressions, respectively: AG1 = -3579-15 T (J/mol) and AGⅡ =6258-24.3 T (J/mol). The results obtained from two different cells are consistent with each other. The results also are in agreement with Rao' s and Tretjakov's data in the measured temperature range. When the Gibbs free energies of formation of MgO and Fe203 were substituted in the reaction, the Gibbs free energies of formation of MgFe204 was obtained in two temperature ranges and the for mations are shown as follows: AG 1Formation =-1427394+360.5 T (J/mol) and AGⅡ Formition =-1417557+351.2 T (J/mol).
文摘The electrochemical formation processes of holmium-cobalt alloys on cobaltcathode in molten HoCl_3-KCl were investigated by cyclic voltammetry and open current potential-timecurve alter potentiostatic electrolysis. The structure of Ho-Co alloys' films deposited on cobaltelectrode by potentiostatic electrolysis was characterized by X-ray diffraction. The standard Gibbsfree energies of formation for the intermetallic compounds of Ho and Co were determined. Thediffusion coefficient and diffusion activation energy of Ho atom in the alloy phase were calculatedto be 10^(-10) -10^(-11) cm^2/s and 96.0 kJ/mol, respectively, from the current-time curve atpotential step.
文摘The electrochemical alloying of Y-Cu system in molten NaCl-KCl-YCl_3 has been investi- gated.The free energy changes of the formation reactions of the intermetallic compounds,in- cluding YCu_6 ,YCu_4 YCu_2 ,Yfu(973—103 K),were determined by means of electrode potential-time curves of the working electrode after potentiostatic electrolysis.The results in- dicate that the potential-time method is simple and reliable.
文摘In this paper it has theoretically proved that the relationship of the molar atomic standard free energies of formation of binary intermediate compounds to the molar fraction of component is a quasi-parabola which is called a quasi-parabolic regula- tion.
文摘The iso-activity of[Ce]of samples reached in multiple-hole-graphite crucibles by controlling the oxygen potential through the reaction 2[Ce]+3CO=Ce_(2)O_(3)+3C.Combining conjugate gradient method of solving ill-conditioned equations,the activity interaction coeffients between Ce and Al.Si,Ti and Fe alloying elements were determined.The equilibrium constant of the reaction 2[Ce]+3[O]=Ce_(2)O_(3)and the standard free energy of formation of Ce203 in liquid Cu were obtained at 1.200 C.
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).
基金the National Natural Science Foundation of China!2890179
文摘The cyclic voltammetry, open current potential-time curve after potentiostatic electrolysis, the currenttime curve at potential step, XRD, EDAX and EPMA were used to study the electrode process of Ho3+ reduction on nickel electrode in molten KCI-HoC13 and the phases of surface alloy layer. The Ho-Ni alloys were deposited when Hos+ was reduced on the nickel electrode. The free energies of formation for the intermetallic compounds between Ho and Ni, the diffusion coefficients and diffusion activation energy of Ho astom in the alloy phase were determined.
文摘The compounds of RESF. RE = La. Ce. Pr, Y and Tb, were made from RE_2S_3 and REF_3 by high tem-perature solid reaction. The Gibbs standard free energies of formation of RESF were measured by galvaniccell technique by using CSZ as solid electrolyte. The results of this work together with the Gibbs standardfree energies of formation ol RE,S. . REzSa and REFa were used to determine the phase diagrams ofRESF systems in this paper.
文摘The combustion energy has been determined for the nine solid complexes of rare earth perchlorate with glycine and imidazole using a rotatingbomb calorimeter.The standard enthalpy of combustion,H0 -c,coor(s), and standard enthalpy of formation,H0 -f,coor(s), for these complexes have been calculated. From the plot of standard enthalpy of formation versus atomic number of the elements in lanthanide series the tripartite effect regularity was observed and the unknown standard enthalpy of formation for similar complexes,Ce(Gly)4(Im)(ClO4)32H2O and Pm(Gly)4(Im)(ClO4)32H2O,can be estimated according to the figure.
基金supported by the National Natural Science Foundation of China(No.U1304111)the Program for Science&Technology Innovation Talents in Universities of Henan Province(No.14HASTIT039)the Innovation Team of Henan University of Science and Technology(2015XTD001)
文摘Based on the full optimized molecular geometric structure at 6-311++G** level,the density(ρ),detonation velocity(D),and detonation pressure(P) for a new furazan-based energetic macrocycle compound,hexakis[1,2,5]oxadi-azole[3,4-c:3',4'-e;3'',4''-g:3''',4'''-k:3'''',4''''-m:3''''',4'''''-o][1,2,9,10]-tetraazacyclohexadecine,were investigated to verify its capacity as high energy density material(HEDM). The infrared spectrum was also predicted. The heat of formation(HOF) was calculated using designed isodesmic reaction. The calculation on the bond dissociation energies(BDEs) was done and the pyrolysis mechanism of the compound was studied. The result shows that the N3–O1 bond in the ring may be the weakest one and the ring cleavage is possible to happen in thermal decomposition. The condensed phase HOF and the crystal density were also calculated for the title compound. The detonation data show that it can be considered as a potential HEDM. These results would provide basic information for the molecular design of novel high energy materials.