Application of annexation principle to the study of thermodynamic properties of Ag—Bi—In metallic melts

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 eutectic which give rise to phase separation,and in which activcities exhibit positive deviation from Raoult‘s law is the basic cause of melts transforming from homogeneous to heterogeneous ones.     

A thermodynamic model of calculating mass action concentrations for structural units or ion couples in NaClO_4-H_2O and NaF-H_2O binary solutions and NaClO_4-NaF-H_2O ternary solution

A thermodynamic model of calculating mass action concentrations for structural units or ion couples in NaClO4-H2O and NaF-H2O binary solutions and NaClO4-NaF-H2O ternary strong electrolyte aqueous solutions was developed based on the ion and molecule coexistence theory (IMCT). A transformation coefficient was needed to compare the calculated mass action concentration and the reported activity, because they were usually obtained at different standard states and concentration units. The results show that transformation coefficients between the calculated mass action concentrations and the reported activities of the same components change in a very narrow range. The transformed mass action concentrations of structural units or ion couples in NaClO4-H2O and NaF-H2O binary solutions agree well with the reported activities. The transformed mass action concentrations of structural units or ion couples in NaClO4-NaF-H2O ternary solution are also in good agreement with the reported activities in a total ionic strength range from 0.1 to 0.9 mol/kg H2O by the 0.1 mol/kg step with different ionic strength fractions of 0, 0.2, 0.4, 0.5, 0.6, 0.8, and 1, respectively. The results indicate that the developed thermodynamic model can reveal the structural characteristics of binary and ternary strong electrolyte aqueous solutions, and the calculated mass action concentrations of structural units or ion couples also strictly follow the mass action law.     

CaO-MgO-MnO-FeO-CaF2-Al2O3-SiO2渣系粘度的计算模型

依据炉渣结构的共存理论与不同温度和成分下熔渣Ｃａｏ－ＭｇＯ－ＭｎＯ－ＦｅＯ－ＣａＦ２－Ａｌ２Ｏ３－ＳｉＯ２的实测粘度制定了本渣系作用浓度和粘度的计算模型,计算结果符合实际证明作用浓度模型可以反映本渣系的实际结构,粘度模型也正确地反映了本渣系粘度与温度及各结构单元作用浓度的正确关系。     

A thermodynamic model of calculating mass action concentrations for structural units or ion couples in NaClO4-H2O and NaF-H2O binary solutions and NaClO4-NaF-H2O ternary solution

A thermodynamic model of calculating mass action concentrations for structural units or ion couples in NaClO₄-H₂O and NaF-H₂O binary solutions and NaClO₄-NaF-H₂O ternary strong electrolyte aqueous solutions was developed based on the ion and molecule coexistence theory (IMCT). A transformation coefficient was needed to compare the calculated mass action concentration and the reported activity, because they were usually obtained at different standard states and concentration units. The results show that transformation coefficients between the calculated mass action concentrations and the reported activities of the same components change in a very narrow range. The transformed mass action concentrations of structural units or ion couples in NaClO₄-H₂O and NaF-H₂O binary solutions agree well with the reported activities. The transformed mass action concentrations of structural units or ion couples in NaClO₄-NaF-H₂O ternary solution are also in good agreement with the reported activities in a total ionic strength range from 0.1 to 0.9 mol/kg H₂O by the 0.1 mol/kg step with different ionic strength fractions of 0, 0.2, 0.4, 0.5, 0.6, 0.8, and 1, respectively. The results indicate that the developed thermodynamic model can reveal the structural characteristics of binary and ternary strong electrolyte aqueous solutions, and the calculated mass action concentrations of structural units or ion couples also strictly follow the mass action law.     

论我国中央企业重组中的企业兼并战略

中央企业之间的兼并战略是诸多企业重组战略中的首选战略。中央企业之间的兼并过程中应该明确兼并的战略目标,兼并后要尽快整合兼并企业和目标企业的所有资源,确保企业兼并后两个企业的总体效益要大于两个独立企业效益的算术和。国务院国资委要根据经济有效原则准确选择适合兼并的中央企业,快速稳妥的促进中央企业之间的兼并。当兼并遇到来自目标企业的非经济原因的阻碍时,应依据产权法理,妥善处理国务院国资委和相关兼并中央企业的关系。     

CaO-MgO-CaF2-Al2O3-SiO2五元渣系粘度的计算模型

依据炉渣结构的共存理论和五元渣系ＣａＯ－ＭｇＯ－ＣａＦ２－ＳｉＯ２－Ａｌ２３在不同温度和成分下的实测粘度值,制定了本渣系的作用浓度和粘度计算模型,计算结果符合实际,证明计算模型可以反映ＣａＯ－ＭｇＯ－ＣａＦ２－Ａｌ２Ｏ３－ＳｉＯ２渣系的实际结构与粘度、结构单元的作用浓度及温度之间的正确关系。     

CaO-Al2O3-SiO2熔渣表面张力的计算模型

根据炉渣结构的共存理论与ＣａＯ－Ａｌ２Ｏ３－ＳｉＯ２熔渣在不同温度和成分下实测表面张力值，制定了本渣系表面张力与熔渣各结构单元作用浓度及温度间关系的计算模型，计算结果符合实际，证明该模型可以反映本渣系表面张力随熔渣作用浓度和温度而变化的规律。     

二元相图中稳定化合物活度的计算方法

基于二元相图中存在大量稳定的化合物的理论基础.据此,提出了一种由含稳定化合物的二元相图中化合物计算活度的新方法.根据已有的从二元相图提取活度的公式,先求出2个组元的活度,再由质量作用定律求出平衡常数K0,从而可由得到的2个纯组元的活度,计算得到稳定化合物的活度.用此方法计算了In-Sb二元系中稳定化合物的活度,经验证此方法是可行的,其计算结果与文献值吻合很好.     

KBr-H2O、NH4Br-H2O和ZnBr2-H2O作用浓度计算模型

建立了强电解质水溶液KBr-H2O、NH4Br-H2O和ZnBr2-H2O作用浓度的计算模型,计算了上述三个溴化物二元水溶液体系在温度为298.15K、质量摩尔浓度达到饱和前的作用浓度.热力学模型计算的组元作用浓度以纯物质为标准态和摩尔分数为浓度单位,与文献报道的组元活度以无限稀为标准态和质量摩尔浓度为浓度单位经过活度的标准态转换后可良好地吻合,且转换系数在计算的浓度范围内基本守恒.以上热力学模型计算的组元作用浓度能反映出强电解质水溶液的结构本质;在本模型的假设下电解质水溶液呈现理想溶液特征,组元的作用浓度在计算的浓度范围内严格遵守质量作用定律.     

三元合金及金属间化合物中各组分活度系数的计算

根据Kohler三元溶体模型和Miedema二元系统生成热模型，建立了计算三元合金及金属化合物中各组分活度系数的方程。计算了三元合金Ti-5Al-2.5Sn,Ti-6Al-4V及不同温度下金属间化合物TiAl,Ti3Al和Ti2AlNb中各组分的活度系数。并与有关实验值进行了对比.计算结果表明此公式的计算结果与实验值吻合较好，解决了固态二元、三元合金及金属间化合物中各组分的活度系数的计算问题，Ti与A1活度系数均小于1，对Raoultl定律产生负偏差。根据所计算的活度系数和活度值，预测了SiC/TiAl,SiC/Ti3Al和SiC/Ti2AlNb复合材料的界面反应，表明SiC/Ti3Al界面反应较为严重。     

Applicability of mass action law to sulphur distribution between slag melts and liquid iron

According to the mass action law and the coexistence theory of slag structure, the calculating models of mass action concentration for CaO-MgO-FeO-Fe₂O₃-SiO₂,CaO-MgO-MnO-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 distribution coefficients between the slag melts and liquid iron are presented.     

基于原子和分子共存理论的Al--Ti熔体反应能力表征

基于原子和分子共存理论建立计算Al- Ti二元合金系结构单元质量作用浓度的热力学模型。利用文献报道的2073、2173和2273 K下Al-Ti二元系的活度计算了生成Al3 Ti、AlTi和Al11 Ti5反应的平衡常数,并进一步得到其标准摩尔吉布斯自由能的表达式。使用文献报道的不同温度下Al-Ti二元合金系全浓度范围内组元Al和Ti的活度aAl和aTi与原子和分子共存理论定义的质量作用浓度NAl和NTi进行比较。结果表明：在Al-Ti二元合金熔体全浓度范围内计算得到的质量作用浓度NAl和NTi与文献报道的活度符合很好。同时,计算得到的Al-Ti二元合金系中结构单元Al3 Ti和Al11 Ti5的平衡物质的量与其质量作用浓度的关系呈“棒状”,而结构单元AlTi的平衡物质的量与其质量作用浓度的关系呈“纺锤”形。     

环形流道变质量流动的静压分布模型

根据动量平衡原理对环形汉道内变质量流动进行一维分析,导出预测环形流道内变质量流动静压分布的计算表达式。预测结果与实验测量值平均相对偏差≤5％。结果表明,采用动量平衡原理对环形流道内变质量流动进步一维分析是适合的。     

基于修正的(NBO/T)比值的黏度模型

针对传统的(NBO/T)比值计算方法在熔渣黏度预报上的不足,研究氧化物对熔渣聚合度的影响规律,修正了(NBO/T)比值的计算方法,计算结果反映了黏度随(NBO/T)比值变化的基本趋势.提出了一个基于修正的(NBO/T)比值的黏度预报模型.利用该模型预报了CaO-SiO2-Al2O3三元系、高炉渣CaO-SiO2-MgO-Al2O3四元系和CaO-SiO2-Al2O3-RO(R2O)体系的黏度值,预报效果比传统的Urbain模型和修改后的Iida模型要好.该模型能有效预报CaO-SiO2-MgO-Al2O3-R2O(K2O或Na2O)体系黏度值.     

Ti_3Al—Nb合金中O相的结构因数及消光规律

对Ｔｉ３Ａｌ—Ｎｂ合金中三元有序和二元有序Ｏ相的结构因数及消光规律进行了理论推导．结果表明．三元有序和二元有序Ｏ相的结构因数表达式不同。但具有相同的消光规律．探讨了用（１１０）和（０２０）的结构因数差别来鉴别三元有序和二元有序Ｏ相的方法．     

Fe－C－O三元金属熔体作用浓度计算模型

根据含化合物的金属熔体结构的共存理论，推导了Ｆｅ－Ｃ－Ｏ金属熔体作用浓度计算模型。计算的Ｎｏ′与相应的实测αｏ相符合，从而证明所得模型可以反映Ｆｅ－Ｃ－Ｏ金属熔体的结构本质。     

The hidden disintegration of cluster heterogeneity in Fe-based glass-forming alloy melt

The evolution of liquid metal at high temperature is known much less than their solid states. This is partially due to that the message concerning clusters, metastable phase or heterogeneity in liquid is usually too slight to be traced. Here, we shed some light on the nature of structural evolution of Fe-based glass-forming alloy during overheating process by the investigation of high-temperature melt viscometry and first principles simulations. It was found that a structural transition around 1400 ℃ occurred in the melts of initial homogeneous ingot, heterogeneous ingot and amorphous ribbons jointly, and was confirmed by the results from differential scanning calorimeter(DSC), and ab initio molecular dynamics(AIMD). Combining these results with Fe-Si-B ternary phase diagram and the melting characteristics of Fe-B compounds, it is safe to conclude that the disintegration of Fe_2B type clusters to Fe_3B-type clusters leads to the observed transition. These results offer a significant reference for the preparation and property control of Fe-based amorphous alloys.     

Atomic-scale computer simulation for early precipitation process of Ni75Al10V15 alloy

The kinetic model for a ternary system is introduced based on the microscopic diffusion form of the phase-field equations for a binary alloy. The equation is solved in the reciprocal space. This model is used to investigate the early precipitation process of Ni75-Al10V15 by simulating the atomic pictures of the two ordered phases and calculating the order parameters of γ′(Ni3Al) phase. Simulation results show that the γ′ ordered phases precipitate from the disordered matrix by a non-classical nucleation mechanism, and the nonstoichiometric γ′ ordered phase appears first and then transforms into the stoichiometric one. Clusters of V atoms appear at the γ′ phase boundaries followed by the formation of the nonstoichiometric θ ordered phase. The farther the location from γ′ phase boundary is, the lower the order degree of θ phase is. There exist two kinds of DO22 ordered domains: a horizontal one and a vertical one, related to their adjacent γ′ phase boundaries. The model could describe the atomic ordering and composition clustering simultaneously, and any a priori assumption about the new phase structure and precipitation mechanism etc. is unnecessary.     

我国警察执法权威消减之困境与出路

警察的执法困境说明我国社会的荣辱观念发生错位、警察执法脱离群众路线、警察自身装备和维权意识淡薄以及警察执法形象被内部违法犯罪行为破坏.我国应在法律上规定袭警行为,对挑战警察执法权威的行为予以严厉打击.     

论业主自治的实现模式之重构

我国住宅小区贯彻业主自治原则。根据现有法律法规,实现业主自治的模式是＂业主大会—业主委员会＂的模式,但这一模式并不适应当下中国的实际,应运用代议制和分权制衡原理成立业主大会、业主代表大会、业主委员会和业主监督委员会等机构,并赋予相应的职权,由此形成＂立业主大会—业主代表大会—业主委员会—业主监督委员会＂的新模式。