micro-XRCT data sets of subflorescent salt crusts from evaporation of MgSO4 solution with 0.32 mol/L initial concentration

This data set contains data of scans of three separated dry salt crusts that formed by evaporation of magnesium sulfate solution with 0.32 mol/L initial concentration from F32 quartz sand at 40%, 30%, and 20% saturation inside the sand packing. The cylindrical sample holder from polymethyl methacrylat (PMMA) had a diameter of 31 mm and a wall thickness of 5 mm. The crusts consisted of sand grains (F32, Quarzwerke Frechen, mean grain size 240 µm), solid salt (particularly magnesium sulfate tetra hydrate), and air. Other magnesium sulfate hydrates may have precipitated (i.e. magnesium sulfate hepta hydrate, hexa hydrate, mono hydrate). The scanned domain with a diameter of 11.76 mm and a resolution of 4 µm per voxel was located in the radial center of the crust. Details of the scan are listed in the process meta data. The reconstructed data is segmented into four phases, outside, void, salt, and sand (for details see below).

本数据集包含三份独立干盐壳的扫描数据，这些盐壳由初始浓度为0.32 mol/L的硫酸镁溶液在F32石英砂中蒸发形成，砂充填体的饱和度分别为40%、30%和20%。实验采用聚甲基丙烯酸甲酯（PMMA）制成的圆柱形样品架，其直径为31 mm，壁厚5 mm。该盐壳由石英砂颗粒（F32，Quarzwerke Frechen公司，平均粒径240 µm）、固态盐（主要为四水硫酸镁）与空气构成，体系中还可能析出其他硫酸镁水合物，包括七水硫酸镁、六水硫酸镁及一水硫酸镁。扫描区域位于盐壳的径向中心，直径为11.76 mm，体素（voxel）分辨率为4 µm。本次扫描的详细信息详见过程元数据。重建后的数据被划分为四个相：外部区域、孔隙、盐相与砂相，详细信息见下文。