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有不同前体的碳化地质聚合物的组成和微结构
1Graduate School of Science and Technology for Innovation, Yamaguchi University, 2-16-1 Tokiwadai, Ube 755-8611, Japan.
Materials (Basel, Switzerland)
|April 13, 2024
概括
由飞灰和渣制成的地质聚合物容易碳化. 碳化形成nahcolite或calcite,混合基地聚合物显示独特的孔堵塞结构,揭示凝组成和变化.
科学领域:
- 材料科学 材料科学 材料科学
- 地质化学 地质化学
- 建筑材料 建筑材料
背景情况:
- 地质聚合物 (GPs) 容易碳化,特别是在环境温度下固化时.
- 了解碳化对地质聚合物矩阵凝组成和微观结构的影响至关重要.
研究的目的:
- 为了研究地质聚合物矩阵凝的组成和微观结构.
- 为了识别飞灰 (FA) 和高炉渣渣 (GGBS) 中产生的地质聚合物中形成的碳化产品.
- 用先进的分析技术分析碳化后地质聚合物的组成变化.
主要方法:
- 使用单独或混合的低FA和GGBS前体制备地质聚合物.
- 样品在20°C时用活性化剂溶液固化,然后进行密封或加速碳化.
- 使用X射线衍射 (XRD),扫描电子显微镜与能量分散X射线光谱 (SEM-EDS) 的分析和三元图分析.
主要成果:
- 碳化产物被识别为纳科利特 (FA 基 GPs) 和 (GGBS 基 GPs).
- 在基于GGBS的GP中,SEM-EDS揭示了立方体形状和小石颗粒,并在基于FA/GGBS混合的GP中发现独特的冰状颗粒.
- 三级图分析证实了冰般的粒子是酸盐和C-A-S-H凝复合体,这些凝堵塞了海绵状C-A-S-H凝中的毛孔.
结论:
- 对S-(C+M+N) -A和A-(C+M) -N的组合三元图分析有效地确定了地质聚合物凝类型和碳化产品.
- C-A-S-H 凝在 (C+M+N) -albite 连接处呈现线性分布,而 N-A-S-H 凝在 S-C+M+N) -A 图中显示分散分布.
- 在A-C+M) -N图中观察到N-A-S-H和C-A-S-H凝的区分区分,有助于理解碳化后的组成变化.
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