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1.
利用 C-CO 控制反应2[Ce]+3CO=Ce_2O_3+3C 的平衡氧位,使多孔石墨坩埚中[Ce]达到等活度的原理,结合解病态方程组的共轭斜量法,求解了1200℃铜液中 Ce 与 Al、Si、Ti、Fe 的活度相互作用系数,得到了反应3[O]+2[Ce]=Ce_2O_3的平衡常数和铜液中 Ce_2O_3的标准生成自由能。  相似文献   

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含有微量O,S,C的Fe—Nb—Ce溶液热力学性质的研究   总被引:2,自引:0,他引:2  
周谦莉  杜挺 《金属学报》1989,25(1):91-95
利用下列组装的固体电解质定氧电池Mo/Cr,Cr_2O_3//ZrO_2(MgO)//[O],Ce_2O_2S/Mo+ZrO_2金属陶瓷,Mo.在1600℃温度下对含微量C的Fe-Nb-Ce溶液进行热力学性质的研究。实验测得1600℃时Fe液中反应Ce_2O_2S=2[Ce]+2[O]+[S]的平衡常数和Ce_2O_2S的标准生成自由能分别为K=4.395×10~(-15),ΔG°_(Ce_2O_2S)=-514.786kJ·mol~(-1);Ce与Nb的活度相互作用系数为e_(Nb)~(Ce)=-2.306,e_(Ce)~(Nb)=-3.481。 随着Nb含量的增加,在微量碳含量的条件下,产物中存在NbC化合物,本文对NbC的生成问题进行了探讨,并得到1600℃时,Fe液中NbC的标准生成自由能为ΔG°_(NbC)=-87.111kJ·mol~(-1)。  相似文献   

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Ce在铁基溶液中分别与Cu,P,Ti相互作用规律的研究SCIEI   总被引:3,自引:0,他引:3  
王跃奎  杜挺 《金属学报》1990,26(3):150-152
Fe-Cu-Ce,Fe-P-Ce和Fe-Ti-Ce溶液的平衡产物是Ce_2O_2S,而不是Ce与Cu、P、Ti的金属间化合物。测定了Fe液中Ce_2O_2S=2[Ce]+[O]+2[S]反应的平衡常数和溶质之间的相互作用系数。Ce降低Cu和Ti在Fe液中的活度,增大其溶解度,同时增大P的活度,降低其溶解度。  相似文献   

4.
Fe—V—Ce溶液的热力学性质研究   总被引:2,自引:0,他引:2  
唱鹤鸣  杜挺  余景生 《金属学报》1989,25(2):152-154
本文研究了在1550—1650℃Fe-V-Ce溶液体系的热力学性质。溶液中微量O,S与Ce建立平衡。已求得Ce与O,S反应的平衡常数。Ce_2O_2S的标准生成自由能及Ce与V的活度相互作用系数与温度的关系。  相似文献   

5.
Cu-Ce-S,Cu-Y-S溶液体系热力学性质的研究SCIEI   总被引:3,自引:0,他引:3  
李国栋  杜挺 《金属学报》1991,27(4):142-144
用化学平衡法研究了1200℃铜液中Ce-S和Y-S的反应平衡。求得Ce和Y的脱硫常数、脱硫产物CeS与YS的标准生成目由能、溶质间活度相互作用系数,Ce和Y在铜液中的标准溶解自由能及其活度系数。  相似文献   

6.
用直接法研究1600℃时溶铁中Ce-S-O平衡关系,测定了Ce的脱氧、脱硫、脱硫氧常数,并进行了有关的热力学探讨.由测得数据算出Ce的溶解自由能(△G_溶~0);活度系数(γ_(Ce)~0);克原子分数和百分浓度的交互作用系数ε_(Ce)~(Ce),e_(Ce)~(Ce);生成Ce_2O_2S的自由能△G_(Ce_2O_2S)~0.  相似文献   

7.
溶铁中Ce-S-O平衡的研究   总被引:1,自引:0,他引:1  
用直接法研究1600℃时溶铁中Ce-S-O平衡关系,测定了Ce的脱氧、脱硫、脱硫氧常数,并进行了有关的热力学探讨.由测得数据算出Ce的溶解自由能(△G_溶~0);活度系数(γ_(Ce)~0);克原子分数和百分浓度的交互作用系数ε_(Ce)~(Ce),e_(Ce)~(Ce);生成Ce_2O_2S的自由能△G_(Ce_2O_2S)~0.  相似文献   

8.
Ni液中Ce-O,Ce-S,Ce-S-O平衡的研究   总被引:1,自引:0,他引:1  
由低温无水电解稀土夹杂物和固体电解质定氧活度测得Ni液中Ce_2O_3,CeS及Ce_2O_2S生成反应的平衡常数,由此可得: △G°_(Ce_2O_3)=-116240+315.8 T △G°_(Ces)=-570280+220.1 T △G°_(Ce_2O_2S)=-984850+238.5 T 由实验测得数据经热力学分析计算得到1600℃Ni液中a_O-a_S平衡图,为理论上预测夹杂物生成的先后次序及类型提供了依据。  相似文献   

9.
王龙妹  杜挺 《金属学报》1987,23(6):553-559
由低温无水电解稀土夹杂物和固体电解质定氧活度测得Ni液中Ce_2O_3,CeS及Ce_2O_2S生成反应的平衡常数,由此可得: △G°_(Ce_2O_3)=-116240+315.8 T △G°_(Ces)=-570280+220.1 T △G°_(Ce_2O_2S)=-984850+238.5 T 由实验测得数据经热力学分析计算得到1600℃Ni液中a_O-a_S平衡图,为理论上预测夹杂物生成的先后次序及类型提供了依据。  相似文献   

10.
纯铁液中Ce-O,Nd-O平衡常数的测定   总被引:1,自引:0,他引:1  
自射线照相表明,铁液中的 Ce,Nd 与 MgO,CaO 坩埚均有明显的作用.在保证Ce,Nd 与坩埚充分作用以达到平衡的条件下,应用放射性同位素~(141)Ce,~(147)Nd 及有机电解液电解法测定了铁液中溶解之 Ce,Nd 含量.用 ZrO_2(MgO)管组成的固体电解质电池测定了铁液中溶解氧的活度.计算出1550—1650℃范围内 Ce-O,Nd-O 平衡常数.对于反应 Ce_2O_(3(s))=2[Ce] 3[O]△G*_(Ce_2O_3)451150-161.68TlgK_(Ce_2O_3)=-(98611)/T 35.34对于反应 Nd_2O_3=2[Nd] 3[O]△G*_(Nd_2O_3)=375010-123.7TlgK_(Nd_2O_3)=-(81970)/T 27.04Nd 溶解于铁液的标准自由能 Nd(1)=[Nd]_(1%)△G*_(Nd)=19790-30.40Tlgγ*_(Nd)=(4326.1)/T-4.154  相似文献   

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The bicyclic cryptand I, 4, 7, 10, 13, 16, 21,24-octaaza-bigcyclo [8, 8, 8] hexacosan-3, 8, 12, 17, 20, 25-hex-one (COBH) bearing diaminoethane groups along the eight-atom bridges was synthesized. The structure consists of discrete neutral macrobicyclic units; the two cycles share the two tertiary amine nitrogen atoms, which exhibit an endo-endo conformation. Three identical branches formed by I, 2-diaminoethane link the two tertiary amine groups. The protonation reactions ofcryptand (COBH) and its complex formation with copper (II) were investigated by potentiometry in water and in a DMSO/water (80: 20 in mass ratio) mixture as solvents. The cryptand acts as a bis-base through its two Nbridgehead and exhibits a strong cooperativity that favors the first protonation and makes the second one difficult (ΔpK≈5.0 ). An inward rotation of the amide groups to form hydrogen bonds accounts for this cooperativity. The interaction of COBH with copper (II) leads to several binuclear complex proton contents.  相似文献   

13.
The bicyclic cryptand 1,4, 7, 10, 13, 16, 21, 24-octaaza-bigcyclo [8, 8, 8] hexacosan-3, 8, 12, 17, 20, 25-hexone (COBH) bearing diaminoethane groups along the eight-atom bridges was synthesized. The structure consists of discrete neutral macrobicyclic units; the two cycles share the two tertiary amine nitrogen atoms, which exhibit an endo-endo conformation. Three identical branches formed by 1, 2-diaminoethane link the two tertiary amine groups. The protonation reactions ofcryptand (COBH) and its complex formation with copper (Ⅱ) were investigated by potentiometry in water and in a DMSO/water (80: 20 in mass ratio) mixture as solvents. The cryptand acts as a bis-base through its two Nbridgehead and exhibits a strong cooperativity that favors the first protonation and makes the second one difficult (pK 5.0 ). An inward rotation of the amide groups to form hydrogen bonds accounts for this cooperativity. The interaction of COBH with copper (Ⅱ) leads to several binuclear complex proton contents.  相似文献   

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Recent literature on Cs-In, Cs-K, Cs-Rb, Eu-In, Ho-Mn, K-Rb, Li-Mg, Mg-Nd, Mg-Zn, Mn-Sm, O-Sb, and Si-Sr phase diagrams is reviewed in this article in order to update the 1990 compilation Binary Alloy Phase Diagrams, 2nd edition, by T.B. Massalski, et al. For some systems reaction tables and crystal structure data have been included, as well. Diagrams have been checked for consistency with rules for phase diagram construction and modified when necessary. In addition, diagrams needing more work have been identified.  相似文献   

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