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1.
Based on the measured activities, the phase diagrams and the annexation principle, the calculating models of mass action concentrations for Ag-Bi and Ag-Bi-In melts have been formulated. The calculated results agree with practice and obey the mass action law, showing that the models formulated can reflect the structural characteristics of both melts. Meanwhile, it confirms that annexation principle is applicable to the Ag-Bi-In metallic melts. The melts involving eulectic which give rise to phase separation, and in which activities exhibit positive deviation from Raoult's law is the basic cause of melts transforming from homogeneous to heterogeneous ones.  相似文献   

2.
Based on the calculating model of metallic melts involving eutectic, the calculating equations of mixing thermodynamic parameters for two phase metallic melts have been formulated in the light of those equations of homogeneous solutions. Irrespective as to whether the activity deviation relative to Raoultian behavior is positive or negative, or the deviation is symmetrical or unsymmetrical, the evaluated results not only agree well with experimental values, but also strictly obey the mass action law. This testifies that these equations can authentically reflect the structural reality and mixing thermodynamic characteristics of two-phase metallic melts. The calculating equations of mixing thermodynamic parameters for the model of two phase metallic melts offer two practical criteria (activity and mixing thermodynamic parameters) and one theoretical criterion (the mass action law).  相似文献   

3.
The calculating models of mass action concentrations for electrolyte aqueous solutions NaBr-H2O, LiNO3-H2O, HNO3-H2O, and KF-H2O have been developed at 298.15 K and their molalities ranging from 0.1 mol/kg to saturation according to the ion and molecule coexistence theory as well as mass action law. The calculated mass action concentration is based on pure species as the standard state and the mole fraction as the concentration unit, and the reported activities are usually based on infinite dilution as the standard state and molality as the concentration unit. Hence, the calculated mass action concentration must be transformed to the same standard state and concentration unit. The transformation coefficients between calculated mass action concentrations and reported ac- tivities of the same component fluctuate in a very narrow range. Thus, the transformed mass action concentrations not only agree well with reported activities, but also strictly obey mass action law. The calculated results show that the new developed models can embody the intrinsic structure of investigated four electrolyte aqueous solutions. The results also indicate that mass action law has its wide- spread applicability to electrolyte binary aqueous solutions.  相似文献   

4.
Based on the phase diagrams, measured activities as well as△Gm and △GXS, calculating models of mass action concentrations for metallic melts involving monotectic have been formulated. The calculated results agree with practice on the whole, showing that the models deduced generally can reflect the structural characteristics of these melts. The metastable compounds formed in the melts are of the types A2B3, AB2, A2B3or AB and A2B3+AB etc..  相似文献   

5.
Based on the phase diagram, the coexistence theory of the metallic melt structure involving compoundformation and the regularity of melts containing saturated phase, a calculating model of mass action concentrationsfor Mn-C melts was formulated. According to the activities (or activity coefficients AM. and γc.), obtained by theUnified Interaction Parameter Model (UIPM), the thermodynamic parameters G and G at higher temperatures (1628~1873 K) were optimized by the repeated try and error method. It is testified that G G(873~1273 K) and G (298~1623 K), obtained at lower temperatures, can also be used at the above-mentionedhigher temperatures. The calculated N. and N agree well with ac. and ac obtained by UIPM. This result showsthat the deduced model can reflect the structural reality of Mn-C melts.  相似文献   

6.
According to the mass action law and the coexistence theroy of slag structure,the calculating models of mass action concentration for CaO-MgO-FeO-Fe2O3-SiO2,CaO-MgO-MgO-FeO-Fe2O3-P2O5-SiO2 and CaO-MgO-MnO-FeO-Fe2O3-Al2O3-P2O5-SiO2 slag melts are formulated and sulphur distribution between the slag melts and liquid iron is treated.It is found that Cao,MnO and FeO promote desulphurization,while MgO is detrimental to desulphurization.In addition.the sulphur sidtribution coefficients between the slag melts and liquid are presented.  相似文献   

7.
Oxidizing Capability of Refining Slags Containing BaO   总被引:1,自引:0,他引:1  
According to the coexistence theory of slag structure melts, the oxidizing capability of the refining slag CaO-MgO-FeO- A12O3SiO2 is studied and the relationship between the mass action concentration of FeO (NFeO) and the activity of FetO (αFetO) for this slag is found to be as NFeo=0.656 1 αFetO. Furthermore, the calculating model of oxidizing capability of the refining slag BaO-CaO-MgO- FeOA12O3-SiO2 is established. A satisfactory result is obtained when using the above oxidizing capability relationship to calculate the desulphurizing capability of such refining BaO-slags.  相似文献   

8.
New formulae for calculating activities and activity coefficients from binary phase diagrams containing solidsolution are presented. In the new formulae, a parameterθ is introduced. It seems be more efficient The application ofthese formulae to system Ag-Pb proves its efficiency.  相似文献   

9.
A gas migration controlling equation was formulated based on the characteristics of the dual pore–fracture media of coal mass and in consideration of the matrix exchange between pores and fractures.A model of permeability dynamic evolution was established by analyzing the variation in effective stress during gas drainage and the action mechanism of the effect of coal matrix desorption on porosity and fracture in the coal body.A coupling model can then be obtained to characterize gas compressibility and coal deformability under the gas–solid coupling of loading coal.In addition,a 3D model of boreholes was established and solved for gas drainage based on the relevant physical parameters of real mines.The comparison and analysis results for the law of gas migration and the evolution of coal body permeability around the boreholes before and after gas extraction between the dual media and the single-seepage field models can provide a theoretical basis for further research on the action mechanism of gas drainage.  相似文献   

10.
The CaO-doped Cu/(NiFe2O4-10NiO) cermet inert anodes were prepared by the cold isostatie pressing-sintering process, and their corrosion resistance to Na3AlF6-K3AlF6-Al203 melt was studied. The results show that the relative density of 5Cu/(NiFe2O4-10NiO) cermet sintered at 1 200 ℃ increases from 82.83% to 97.63% when 2% CaO (mass fraction) is added. During the electrolysis, the relative density of cermet inert anode descends owing to the chemical dissolution of additive CaO at ceramic grain boundary, which accelerates the penetration of electrolyte. Thus, the corrosion resistance to melts of Cu/(NiFe2O4-10NiO) cermet inert anode is reduced. To improve the corrosion resistance of the cermet inert anode, the content of CaO doped should be decreased and the technology of cleaning the ceramic grain boundary should be applied.  相似文献   

11.
A universal thermodynamic model of calculating the mass action concentrations of components in a ternary strong elec-trolyte aqueous solution has been developed based on the ion and molecule coexistence theory, and verified in the NaCl-KCl-H2Oternary system at 298.15 K, To compare the difference of the thermodynamic model in binary and ternary strong electrolyte aqueous solutions, the mass action concentrations of components in the NaCI-H20 binary strong electrolyte aqueous solution were also com-puted at 298.15K. A transformation coefficient was required to compare the calculated mass action concentration and reported activ-ity because they were obtained at different standard states and concentration units. The results show that the transformation coeffi-cients between calculated mass action concentrations and reported activities of the same components change in a very narrow range.The calculated mass action concentrations of components in the NaCl-H2O and NaCl-KCl-H2O systems are in good agreement with the reported activities. This indicates that the developed thermodynamic model can reflect the structural characteristics of solutions,and the mass action concentration also strictly follows the mass action law.  相似文献   

12.
A universal thermodynamic model of calculating the mass action concentrations of components in a ternary strong electrolyte aqueous solution has been developed based on the ion and molecule coexistence theory, and verified in the NaCl-KCl-H2O ternary system at 298.15 K. To compare the difference of the thermodynamic model in binary and ternary strong electrolyte aqueous solutions, the mass action concentrations of components in the NaCl-H2O binary strong electrolyte aqueous solution were also computed at 298.15K. A transformation coefficient was required to compare the calculated mass action concentration and reported activity because they were obtained at different standard states and concentration units. The results show that the transformation coefficients between calculated mass action concentrations and reported activities of the same components change in a very narrow range. The calculated mass action concentrations of components in the NaCl-H2O and NaCl-KCl-H2O systems are in good agreement with the reported activities. This indicates that the developed thermodynamic model can reflect the structural characteristics of solutions, and the mass action concentration also strictly follows the mass action law.  相似文献   

13.
According to the mass action law and the coexistence theory of metallic melts, the mass action concentrations of Cu-Mg, Bi T1 and Ni-Al melts involving compound formation have been calculated. The calculated results show that, except the ultimate case of pure element, when two elements are present in the melts, all structural units (atoms and molecules) without exception will be present in the melts, i.e., their concentrations may change from great to small, but they will not vanish into nothing, and only under such conditions, the calculated results both agree with practice and obey the law of mass action. In view of that over considerable wide composition range, the activities of both elements of the three solid binary alloys mentioned above have been measured, this seems in contradiction with the present relevant phase diagrams, in which the structural units are determined by composition range, so the latter needs further investigation and consideration.  相似文献   

14.
According to phase diagrams, measured activities as well as the coexistence theory of metallic melts structure involving compound formation, the calculating models of mass action concentrations for Ni-Mn and Co-Mn melts are formulated and their thermodynamic parameters are optimized. As a result, the calculated mass action concentrations agree well with the corresponding measured activities, showing that these models can reflect the structural characteristics of both Ni-Mn and Co-Mn melts.  相似文献   

15.
A universal thermodynamic model of calculating the mass action concentrations of components in a ternary strong elec-trolyte aqueous solution has been developed based on the ion and molecule coexistence theory,and verified in the NaCl-KCl-H2O ternary system at 298.15 K. To compare the difference of the thermodynamic model in binary and ternary strong electrolyte aqueous solutions,the mass action concentrations of components in the NaCl-H2O binary strong electrolyte aqueous solution were also com-puted at 29...  相似文献   

16.
Based on the phase diagrams, reliable reference experimental data and the coexistence theory of metallic melts structure involving compound formation, calculating models of mass action concentrations for Fe-P and Cr-P melts have been formulated. At the same time, some of their thermodynamic parameters have been optimized. The calculated results not only agree well with the measuredvalues, but also obey the mass action law rigorously, this in turn shows that these models can reflect the structural characteristics of corresponding melts.  相似文献   

17.
张鉴 《包头钢铁学院学报》2001,20(3):214-218,231
根据相图、质量作用定律和金属熔体结构的共存理论制定了Mg-Al,Sr-Al和Ba-Al熔体的作用浓度计算模型并求得了相关的热力学参数,计算结果符合实际,证明所制定的模型和确定的热力学参数可以反映相应熔体的结构特点,但将相应文献的热力学参数代入同样熔体则未取得符合实际的结果,原因可能与文献中的热力学参数不符合液态下金属熔体内部化学反应的实际有关。  相似文献   

18.
根据混合自由能有最小值,过剩自由能有最大值(或最小值),激冷条件下产生化合物状亚稳相及共晶,分层等现象,针对Cd-Bi,Ge-Al,Bi-Sn,Cd-Sn,Ag-Cu,Al-Ga;Si-Ag,Pb-Sn和Al-Sn金属熔体推导了作用浓度的计算模型,计算结果与实测值符合较好,从而证明所提出的计算模型符合本类熔体的结构特点。  相似文献   

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