Calorimetric study of olivine solid solutions in the system Mg2SiO4-Fe2SiO4
Calorimetric study of olivine solid solutions in the system Mg2SiO4-Fe2SiO4
复制标题
Mg2SiO4-Fe2SiO4体系中橄榄石固溶体的量热研究
DOI：
10.1007/bf00211849
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发表时间：
1994
影响因子：
1.4
通讯作者：
M. Akaogi
中科院分区：
文献类型：
--
作者：
H. Kojitani;M. Akaogi
在979 K下，测量了Mg 2SiO 4-Fe 2SiO 4系统中人工合成的橄榄石固溶体在2 PbO·B2 O3熔体中的溶解度。的焓数据表明，橄榄石固溶体具有正的混合焓和理想的偏差近似为对称相对于组合物，在以前的研究相反。应用对称正规溶液模型计算了乙醇吡啶的相互作用参数为5.3± 1.7kJ/mol（单阳离子中心基）。利用这一结果和已发表的过量混合自由能数据，估算出橄榄石固溶体的非理想熵参数为0.6± 1.5J/mol·K。
Solution enthalpies of synthetic olivine solid solutions in the system Mg2SiO4-Fe2SiO4have been measured in molten 2PbO·B2O3at 979 K. The enthalpy data show that olivine solid solutions have a positive enthalpy of mixing and the deviation from ideality is approximated as symmetric with respect to composition, in contrast to the previous study. Applying the symmetric regular solution model to the present enthalpy data, the interaction parameter of ethalpy (WH) is estimated to be 5.3±1.7 kJ/mol (one cation site basis). Using this Whand the published data on excess free energy of mixing, the nonideal parameter of entropy (Ws) of olivine solid solutions is estimated as 0.6±1.5 J/mol·K.