通过诱导的CaCO3沉来探索一种具有高尿酶活性的Bacillus cereus,用于通过诱导的CaCO3沉来进行自愈混凝土
Jian-Miao Xu1,2, Wei-Jie Wang1,2, Zhuo-Ting Chen1,2
1Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, The National and Local, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou, 310014, China.
Applied microbiology and biotechnology
|August 22, 2023
概括
使用Bacillus cereus的微生物诱导的碳酸沉有效地修复了混凝土裂. 这种方法显示超过90%的裂修复,即使在恶劣的性和高盐条件下.
科学领域:
- 材料科学 材料科学 材料科学
- 微生物学 微生物学
- 土木工程 土木工程是指土木工程.
背景情况:
- 混凝土裂损害了结构完整性和美学.
- 微生物诱导的碳酸沉 (MICP) 为混凝土修复提供了一个有前途的解决方案.
- 生产尿酶的微生物是MICP的关键,其中Bacillus cereus显示出高尿酶活性.
研究的目的:
- 通过MICP评估Bacillus cereus在修复混凝土裂方面的有效性.
- 为了评估Bacillus cereus在性和高盐度环境中的表现.
- 为了确定碳糖甲基纤维素 (CMC-Na) 作为MICP的加厚剂的最佳度.
主要方法:
- 从土壤中分离Bacillus cereus,基于高尿酶活性.
- 测试菌株对性介质 (pH13) 和高盐度 (4%) 的耐受性.
- 评估使用不同度的四种不同的加厚剂的裂纹修复效率,重点是CMC-Na.
主要成果:
- 在pH 13和4%的盐度下,Bacillus cereus表现出强的生长.
- 最佳的裂纹修复得到了10g/L的碳素甲基纤维素 (CMC-Na).
- 这种系统导致90%以上的裂修复,最初的水透时间为30秒.
结论:
- 谷菌是一种可行的微生物,用于基于MICP的混凝土裂修复.
- 这种菌株对极端条件的耐受性使其适合于充满挑战的环境.
- 使用CMC-Na优化的MICP显著提高了混凝土的结构完整性.
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