Methods The trend-surface regressional model was based on multiple regression. Then trend-surfacediagram was drawed according to the mathematical model.
方法以多元回归分析理论为基础，构造趋势面回归数学模型，并依据模型方程绘制趋势面层次分析图。
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A graphic method for representing thermochemical data was proposed, i. e. the equilibrium surfacediagram, which is useful for hydrometallurgical studies.
In actual application, one should complicate the simple diagram, make single diagram successive, sterolize the surfacediagram and take the static diagram as a mobile one.